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Nanomedicine – Wikipedia

Nanomedicine is the medical application of nanotechnology.[1] Nanomedicine ranges from the medical applications of nanomaterials and biological devices, to nanoelectronic biosensors, and even possible future applications of molecular nanotechnology such as biological machines. Current problems for nanomedicine involve understanding the issues related to toxicity and environmental impact of nanoscale materials (materials whose structure is on the scale of nanometers, i.e. billionths of a meter).

Functionalities can be added to nanomaterials by interfacing them with biological molecules or structures. The size of nanomaterials is similar to that of most biological molecules and structures; therefore, nanomaterials can be useful for both in vivo and in vitro biomedical research and applications. Thus far, the integration of nanomaterials with biology has led to the development of diagnostic devices, contrast agents, analytical tools, physical therapy applications, and drug delivery vehicles.

Nanomedicine seeks to deliver a valuable set of research tools and clinically useful devices in the near future.[2][3] The National Nanotechnology Initiative expects new commercial applications in the pharmaceutical industry that may include advanced drug delivery systems, new therapies, and in vivo imaging.[4] Nanomedicine research is receiving funding from the US National Institutes of Health, including the funding in 2005 of a five-year plan to set up four nanomedicine centers.

Nanomedicine sales reached $16 billion in 2015, with a minimum of $3.8 billion in nanotechnology R&D being invested every year. Global funding for emerging nanotechnology increased by 45% per year in recent years, with product sales exceeding $1 trillion in 2013.[5] As the nanomedicine industry continues to grow, it is expected to have a significant impact on the economy.

Nanotechnology has provided the possibility of delivering drugs to specific cells using nanoparticles.

The overall drug consumption and side-effects may be lowered significantly by depositing the active agent in the morbid region only and in no higher dose than needed. Targeted drug delivery is intended to reduce the side effects of drugs with concomitant decreases in consumption and treatment expenses. Drug delivery focuses on maximizing bioavailability both at specific places in the body and over a period of time. This can potentially be achieved by molecular targeting by nanoengineered devices.[6][7] More than $65 billion are wasted each year due to poor bioavailability.[citation needed] A benefit of using nanoscale for medical technologies is that smaller devices are less invasive and can possibly be implanted inside the body, plus biochemical reaction times are much shorter. These devices are faster and more sensitive than typical drug delivery.[8] The efficacy of drug delivery through nanomedicine is largely based upon: a) efficient encapsulation of the drugs, b) successful delivery of drug to the targeted region of the body, and c) successful release of the drug.[citation needed]

Drug delivery systems, lipid- [9] or polymer-based nanoparticles,[10] can be designed to improve the pharmacokinetics and biodistribution of the drug.[11][12][13] However, the pharmacokinetics and pharmacodynamics of nanomedicine is highly variable among different patients.[14] When designed to avoid the body's defence mechanisms,[15] nanoparticles have beneficial properties that can be used to improve drug delivery. Complex drug delivery mechanisms are being developed, including the ability to get drugs through cell membranes and into cell cytoplasm. Triggered response is one way for drug molecules to be used more efficiently. Drugs are placed in the body and only activate on encountering a particular signal. For example, a drug with poor solubility will be replaced by a drug delivery system where both hydrophilic and hydrophobic environments exist, improving the solubility.[16] Drug delivery systems may also be able to prevent tissue damage through regulated drug release; reduce drug clearance rates; or lower the volume of distribution and reduce the effect on non-target tissue. However, the biodistribution of these nanoparticles is still imperfect due to the complex host's reactions to nano- and microsized materials[15] and the difficulty in targeting specific organs in the body. Nevertheless, a lot of work is still ongoing to optimize and better understand the potential and limitations of nanoparticulate systems. While advancement of research proves that targeting and distribution can be augmented by nanoparticles, the dangers of nanotoxicity become an important next step in further understanding of their medical uses.[17]

Nanoparticles can be used in combination therapy for decreasing antibiotic resistance or for their antimicrobial properties.[18][19][20] Nanoparticles might also used to circumvent multidrug resistance (MDR) mechanisms.[21]

Two forms of nanomedicine that have already been tested in mice and are awaiting human trials that will be using gold nanoshells to help diagnose and treat cancer,[22] and using liposomes as vaccine adjuvants and as vehicles for drug transport.[23][24] Similarly, drug detoxification is also another application for nanomedicine which has shown promising results in rats.[25] Advances in Lipid nanotechnology was also instrumental in engineering medical nanodevices and novel drug delivery systems as well as in developing sensing applications.[26] Another example can be found in dendrimers and nanoporous materials. Another example is to use block co-polymers, which form micelles for drug encapsulation.[10]

Polymeric nano-particles are a competing technology to lipidic (based mainly on Phospholipids) nano-particles. There is an additional risk of toxicity associated with polymers not widely studied or understood. The major advantages of polymers is stability, lower cost and predictable characterisation. However, in the patient's body this very stability (slow degradation) is a negative factor. Phospholipids on the other hand are membrane lipids (already present in the body and surrounding each cell), have a GRAS (Generally Recognised As Safe) status from FDA and are derived from natural sources without any complex chemistry involved. They are not metabolised but rather absorbed by the body and the degradation products are themselves nutrients (fats or micronutrients).[citation needed]

Protein and peptides exert multiple biological actions in the human body and they have been identified as showing great promise for treatment of various diseases and disorders. These macromolecules are called biopharmaceuticals. Targeted and/or controlled delivery of these biopharmaceuticals using nanomaterials like nanoparticles and Dendrimers is an emerging field called nanobiopharmaceutics, and these products are called nanobiopharmaceuticals.[citation needed]

Another highly efficient system for microRNA delivery for example are nanoparticles formed by the self-assembly of two different microRNAs deregulated in cancer.[27]

Another vision is based on small electromechanical systems; nanoelectromechanical systems are being investigated for the active release of drugs. Some potentially important applications include cancer treatment with iron nanoparticles or gold shells.Nanotechnology is also opening up new opportunities in implantable delivery systems, which are often preferable to the use of injectable drugs, because the latter frequently display first-order kinetics (the blood concentration goes up rapidly, but drops exponentially over time). This rapid rise may cause difficulties with toxicity, and drug efficacy can diminish as the drug concentration falls below the targeted range.[citation needed]

Some nanotechnology-based drugs that are commercially available or in human clinical trials include:

Existing and potential drug nanocarriers have been reviewed.[38][39][40][41]

Nanoparticles have high surface area to volume ratio. This allows for many functional groups to be attached to a nanoparticle, which can seek out and bind to certain tumor cells. Additionally, the small size of nanoparticles (10 to 100 nanometers), allows them to preferentially accumulate at tumor sites (because tumors lack an effective lymphatic drainage system).[42] Limitations to conventional cancer chemotherapy include drug resistance, lack of selectivity, and lack of solubility. Nanoparticles have the potential to overcome these problems.[43]

In photodynamic therapy, a particle is placed within the body and is illuminated with light from the outside. The light gets absorbed by the particle and if the particle is metal, energy from the light will heat the particle and surrounding tissue. Light may also be used to produce high energy oxygen molecules which will chemically react with and destroy most organic molecules that are next to them (like tumors). This therapy is appealing for many reasons. It does not leave a "toxic trail" of reactive molecules throughout the body (chemotherapy) because it is directed where only the light is shined and the particles exist. Photodynamic therapy has potential for a noninvasive procedure for dealing with diseases, growth and tumors. Kanzius RF therapy is one example of such therapy (nanoparticle hyperthermia) .[citation needed] Also, gold nanoparticles have the potential to join numerous therapeutic functions into a single platform, by targeting specific tumor cells, tissues and organs.[44][45]

In vivo imaging is another area where tools and devices are being developed. Using nanoparticle contrast agents, images such as ultrasound and MRI have a favorable distribution and improved contrast. This might be accomplished by self assembled biocompatible nanodevices that will detect, evaluate, treat and report to the clinical doctor automatically.[citation needed]

The small size of nanoparticles endows them with properties that can be very useful in oncology, particularly in imaging. Quantum dots (nanoparticles with quantum confinement properties, such as size-tunable light emission), when used in conjunction with MRI (magnetic resonance imaging), can produce exceptional images of tumor sites. Nanoparticles of cadmium selenide (quantum dots) glow when exposed to ultraviolet light. When injected, they seep into cancer tumors. The surgeon can see the glowing tumor, and use it as a guide for more accurate tumor removal.These nanoparticles are much brighter than organic dyes and only need one light source for excitation. This means that the use of fluorescent quantum dots could produce a higher contrast image and at a lower cost than today's organic dyes used as contrast media. The downside, however, is that quantum dots are usually made of quite toxic elements.[citation needed]

Tracking movement can help determine how well drugs are being distributed or how substances are metabolized. It is difficult to track a small group of cells throughout the body, so scientists used to dye the cells. These dyes needed to be excited by light of a certain wavelength in order for them to light up. While different color dyes absorb different frequencies of light, there was a need for as many light sources as cells. A way around this problem is with luminescent tags. These tags are quantum dots attached to proteins that penetrate cell membranes. The dots can be random in size, can be made of bio-inert material, and they demonstrate the nanoscale property that color is size-dependent. As a result, sizes are selected so that the frequency of light used to make a group of quantum dots fluoresce is an even multiple of the frequency required to make another group incandesce. Then both groups can be lit with a single light source. They have also found a way to insert nanoparticles[46] into the affected parts of the body so that those parts of the body will glow showing the tumor growth or shrinkage or also organ trouble.[47]

Nanotechnology-on-a-chip is one more dimension of lab-on-a-chip technology. Magnetic nanoparticles, bound to a suitable antibody, are used to label specific molecules, structures or microorganisms. Gold nanoparticles tagged with short segments of DNA can be used for detection of genetic sequence in a sample. Multicolor optical coding for biological assays has been achieved by embedding different-sized quantum dots into polymeric microbeads. Nanopore technology for analysis of nucleic acids converts strings of nucleotides directly into electronic signatures.[citation needed]

Sensor test chips containing thousands of nanowires, able to detect proteins and other biomarkers left behind by cancer cells, could enable the detection and diagnosis of cancer in the early stages from a few drops of a patient's blood.[48]Nanotechnology is helping to advance the use of arthroscopes, which are pencil-sized devices that are used in surgeries with lights and cameras so surgeons can do the surgeries with smaller incisions. The smaller the incisions the faster the healing time which is better for the patients. It is also helping to find a way to make an arthroscope smaller than a strand of hair.[49]

Research on nanoelectronics-based cancer diagnostics could lead to tests that can be done in pharmacies. The results promise to be highly accurate and the product promises to be inexpensive. They could take a very small amount of blood and detect cancer anywhere in the body in about five minutes, with a sensitivity that is a thousand times better than in a conventional laboratory test. These devices that are built with nanowires to detect cancer proteins; each nanowire detector is primed to be sensitive to a different cancer marker. The biggest advantage of the nanowire detectors is that they could test for anywhere from ten to one hundred similar medical conditions without adding cost to the testing device.[50] Nanotechnology has also helped to personalize oncology for the detection, diagnosis, and treatment of cancer. It is now able to be tailored to each individuals tumor for better performance. They have found ways that they will be able to target a specific part of the body that is being affected by cancer.[51]

Magnetic micro particles are proven research instruments for the separation of cells and proteins from complex media. The technology is available under the name Magnetic-activated cell sorting or Dynabeads among others. More recently it was shown in animal models that magnetic nanoparticles can be used for the removal of various noxious compounds including toxins, pathogens, and proteins from whole blood in an extracorporeal circuit similar to dialysis.[52][53] In contrast to dialysis, which works on the principle of the size related diffusion of solutes and ultrafiltration of fluid across a semi-permeable membrane, the purification with nanoparticles allows specific targeting of substances. Additionally larger compounds which are commonly not dialyzable can be removed.[citation needed]

The purification process is based on functionalized iron oxide or carbon coated metal nanoparticles with ferromagnetic or superparamagnetic properties.[54] Binding agents such as proteins,[53]antibodies,[52]antibiotics,[55] or synthetic ligands[56] are covalently linked to the particle surface. These binding agents are able to interact with target species forming an agglomerate. Applying an external magnetic field gradient allows exerting a force on the nanoparticles. Hence the particles can be separated from the bulk fluid, thereby cleaning it from the contaminants.[57][58]

The small size (< 100nm) and large surface area of functionalized nanomagnets leads to advantageous properties compared to hemoperfusion, which is a clinically used technique for the purification of blood and is based on surface adsorption. These advantages are high loading and accessibility of the binding agents, high selectivity towards the target compound, fast diffusion, small hydrodynamic resistance, and low dosage.[59]

This approach offers new therapeutic possibilities for the treatment of systemic infections such as sepsis by directly removing the pathogen. It can also be used to selectively remove cytokines or endotoxins[55] or for the dialysis of compounds which are not accessible by traditional dialysis methods. However the technology is still in a preclinical phase and first clinical trials are not expected before 2017.[60]

Nanotechnology may be used as part of tissue engineering to help reproduce or repair or reshape damaged tissue using suitable nanomaterial-based scaffolds and growth factors. Tissue engineering if successful may replace conventional treatments like organ transplants or artificial implants. Nanoparticles such as graphene, carbon nanotubes, molybdenum disulfide and tungsten disulfide are being used as reinforcing agents to fabricate mechanically strong biodegradable polymeric nanocomposites for bone tissue engineering applications. The addition of these nanoparticles in the polymer matrix at low concentrations (~0.2 weight%) leads to significant improvements in the compressive and flexural mechanical properties of polymeric nanocomposites.[61][62] Potentially, these nanocomposites may be used as a novel, mechanically strong, light weight composite as bone implants.[citation needed]

For example, a flesh welder was demonstrated to fuse two pieces of chicken meat into a single piece using a suspension of gold-coated nanoshells activated by an infrared laser. This could be used to weld arteries during surgery.[63] Another example is nanonephrology, the use of nanomedicine on the kidney.

Neuro-electronic interfacing is a visionary goal dealing with the construction of nanodevices that will permit computers to be joined and linked to the nervous system. This idea requires the building of a molecular structure that will permit control and detection of nerve impulses by an external computer. A refuelable strategy implies energy is refilled continuously or periodically with external sonic, chemical, tethered, magnetic, or biological electrical sources, while a nonrefuelable strategy implies that all power is drawn from internal energy storage which would stop when all energy is drained. A nanoscale enzymatic biofuel cell for self-powered nanodevices have been developed that uses glucose from biofluids including human blood and watermelons.[64] One limitation to this innovation is the fact that electrical interference or leakage or overheating from power consumption is possible. The wiring of the structure is extremely difficult because they must be positioned precisely in the nervous system. The structures that will provide the interface must also be compatible with the body's immune system.[65]

Molecular nanotechnology is a speculative subfield of nanotechnology regarding the possibility of engineering molecular assemblers, machines which could re-order matter at a molecular or atomic scale. Nanomedicine would make use of these nanorobots, introduced into the body, to repair or detect damages and infections. Molecular nanotechnology is highly theoretical, seeking to anticipate what inventions nanotechnology might yield and to propose an agenda for future inquiry. The proposed elements of molecular nanotechnology, such as molecular assemblers and nanorobots are far beyond current capabilities.[1][65][66][67] Future advances in nanomedicine could give rise to life extension through the repair of many processes thought to be responsible for aging. K. Eric Drexler, one of the founders of nanotechnology, postulated cell repair machines, including ones operating within cells and utilizing as yet hypothetical molecular machines, in his 1986 book Engines of Creation, with the first technical discussion of medical nanorobots by Robert Freitas appearing in 1999.[1]Raymond Kurzweil, a futurist and transhumanist, stated in his book The Singularity Is Near that he believes that advanced medical nanorobotics could completely remedy the effects of aging by 2030.[68] According to Richard Feynman, it was his former graduate student and collaborator Albert Hibbs who originally suggested to him (circa 1959) the idea of a medical use for Feynman's theoretical micromachines (see nanotechnology). Hibbs suggested that certain repair machines might one day be reduced in size to the point that it would, in theory, be possible to (as Feynman put it) "swallow the doctor". The idea was incorporated into Feynman's 1959 essay There's Plenty of Room at the Bottom.[69]

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Diet Science by Dee and Michael McCaffrey on iTunes

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We are unable to find iTunes on your computer. To download and subscribe to Diet Science by Dee and Michael McCaffrey, get iTunes now.

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Diet Science is a fun 7 to 8 minute weekly program with insights and straight scoops on today's health and diet issues from Dee McCaffrey, CDC. Dee is an Organic Chemist who lost 100 pounds, nearly half her body weight, and has kept it off for 20 years by staying away from processed foods. She's the author of The Science of Skinny, released by Perseus June 2012, and The Science of Skinny Cookbook, which was released December 2014.

I love this podcast, and you should try it out, too! I am so tired of fad advice when it comes to nutrition and diet, and "Diet Science" is the opposite. I can't wait for each new episode. All of the information in this podcast is science-based, and will open your eyes to what you are really putting into your body. And, unlike many other podcasts, each episode contains worthwhile information, rather than a 'promo' for information you need to buy. Because of the new information I have found here, I am slowly guiding my family's diet to be more healthy. Right now we are experimenting with quinoa, and I look forward to trying flax oil next!

Great information presented in such a way even a "beginner" like me can understand it! "Mighty Dee" is a life-saver to me! Her podcasts have become my "bible" to healthy eating. There is so much information out there it gets so confusing just trying to figure out what and who to believe! As soon as you listen to ONE of Dee's podcasts you will become a "believer"! I have lost 15 pounds in 4 weeks using Dee's advice and guidelines. She has the education, the knowledge and personal experience and she willingly shares it all.

...and not those topics you are uninformed about. Your podcast on orthorexia demonstrated your lack of knowledge when it comes to eating disorders - and Michael's insensitivity towards people who suffer from this mental illness was disturbing. (Though he did "come around" towards the end of the episode.) Dee's comments clearly showed her ignorance of the topic, and were more damaging than helpful. Stick to what you "know" and do NOT dabble in content where you are uninformed/uneducated/unaware.

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Buy Sermorelin Injections | Buy Sermorelin Online

It is now possible to buy sermorelin injections online and have them shipped directly to your home or office. The ability to buy sermorelin online does not change the fact that a prescription is required by a licensed Physician. Just as with any other type of prescription medication, a licensed Physician must determine there is a medical necessity for a prescription to be issued. The same applies to sermorelin. This is not a medication that should be prescribed unless there is a true need for it, in adults, that reason would be reduced levels of natural HGH production. Laboratory testing is a sure way to determine if this is the case. A physical examination is also required to rule out the possibility of any other causes for present symptoms. The final requirement is a patient medical history. If a true deficiency is diagnosed, it will then be possible to buy sermorelin injections online.

1. First, complete a contact form, one of our wellness consultants will contact you soon after. The wellness consultant will discuss all the details of hormone replacement therapy as well as answer any questions or concerns you may have.

2. Your wellness consultant will then schedule both a blood test and physical exam in your local area. You will also be required to complete a new patient medical history.

3. Upon completion of steps 1 and 2, one of our Physicians will review your results to determine if a hormone deficiency or imbalance exists. If it is determined a deficiency or imbalance is present, the Physician will determine the most effective hormone replacement therapy program for you.

4. The prescription(s) for the appropriate medication are sent directly to the pharmacy. These medications are shipped overnight to your home or office. One of our highly trained staff will guide you step by step through the instructions, injection procedure and program schedule.

Choosing an educated and specialized provider of hormone replacement therapy, as well as the safest and most effective method of treatment, is very important. While some seek hormone therapy through their family Doctor, this is rarely as comprehensive and effective as treatment from a specialized hormone Doctor. Family Doctors, if they are even open to prescribing hormone therapy, typically lack the understanding and thoroughness of a hormone specialist.

A generic method of hormone replacement therapy is never the answer. With Elite HRT, you will receive a completely personalized hormone replacement therapy program. Designed specifically for you, the benefits and safety of your treatment will far exceed any of the generic methods of treatment available today.

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Anti-aging medicine – National Center for Biotechnology …

Today's healthcare challenges and tomorrow's opportunity can only be met by those who search out deeper explanations of the body processes that generate health and disease. Life expectancy has increased due to advances in medical science. However it has come with little progress towards quality of life or the length of disease-free years in the majority of population.

Most researchers believe that maximum life span in human is slightly over 110 years. Beyond that age, the estimates and speculation enter the realms of science fiction.

Old age is the most unexpected of all things that happens to man. -

Leon Trotsky

Aging has been a fact of life ever since it was created. Human beings go through various phases of life from being child to youth to being adult with youth being the best part of life from health point of view. Good health, strong muscles, an efficient immune system, a sharp memory and a healthy brain are characteristic of ideal youth. The hormones work at their peak capacity during the youth years.

Anti-Aging medicine aims to maintain or achieve this irrespective of chronological age i.e. to stay healthy and biologically efficient.

The prestigious scientific journal, Biogerontology, defines aging as: The progressive failing ability of the body's own intrinsic and genetic powers to defend, maintain and repair itself in order to keep working efficiently.

We are now living in the information age. Medical knowledge is increasing at an amazing rate-doubling every three years. This doubling rate of information is progressively decreasing. The world is changing and so is the way we view our health and well being as we age.

Aging has been believed to be inherent, universal, progressive natural phenomenon. It is detrimental with no benefits except perhaps wisdom. But now there is a paradigm shift in looking at the aging process based on firmly documented evidence in medical and scientific literature. If we plot the health in y-axis and the number of years in x-axis, the curve of life is like a triangle which is skewed with its apex at 25-30 years. Anti-aging helps to make it rectangle.

Many natural aging mechanisms frequently result in actual diseases. From this we can conclude that fighting an aging process may well bring about an improvement of an age related illness.

All animals or plants eventually show signs of aging even if they are in a protected environment. When we look at Ayurveda which prescribes plants or their components and extracts to fight against illness, one has to wonder why? Nature created these plant chemicals to help them protect against diseases or aging. Humans have later adapted these chemicals for their own use to increase their chances of maintaining their health.

Anti-aging medicine is an evolving branch of medical science and applied medicine. It treats the underlying causes of aging and aims at alleviating any age related ailment. Its goal is to extend the healthy lifespan of humans having youthful characteristics.

Conventional and alternative medical disciplines are used in an integrated approach to achieve the best possible result for the patient. It is a holistic discipline, seeing the patient as a whole and not as someone having an isolated disease.

Those physicians interested in studying age related medicine can do so by attending courses offered by various organization across the globe with predominant being The American Academy of Anti-Aging Medicine or A4M. It is not yet formally accredited by the American Medical Association. Some scientists and physicians take offense at the name Anti-Aging as they think it is unscientific. They have suggested terms such as Age Management Medicine, Advanced Preventive Medicine, Interventive Biogerontology. But the underlying principles remain the same.

Aging is a progressive failure of metabolic processes. There is a concept of pause as put forth by Dr. Eric Braverman indicating that every organ ages at a different rate. To a certain extent it is based on hormones. All these have been put forth into various theories as follows:

Free Radical Theory

The Nuroendocrine Theory

Telomerase Theory of Aging

The Wear and Tear Theory

The Rate of Living Theory

The Waste Product Accumulation Theory

The Cross-linking Theory

The Immune Theory

Theories of Errors and Repairs

The Order to Disorder Theory

Some of these contradict and others overlap. But underlying these are three main biochemical processes involved in aging. These are oxidation, glycation and methylation. Other relevant processes are chronic inflammation and hormonal deregulation.

Free radicals are a group of simple compounds with an electron missing from their chemical structure. This makes them unstable. They seek out other chemical structures from which they can acquire an electron and in the process make them unstable.

Free radicals in small and controlled quantities are useful in everyday metabolism. They take part in several normal reactions within the body including breathing. These free radicals are mainly produced during oxygen metabolism within the cells. The problem starts when the production of these free radicals increases and goes out of control.

Free radical reactions can be divided into three stages: Initiation, Propagation and Termination. The defense mechanisms against these are inactivating them within the cells soon after production, removing them by scavenging antioxidants and increasing the elimination of material already damaged by free radicals.

To put it in practice means to prevent exposure to free radicals from sources such as pollution, bad diet, and smoking and take antioxidants. The term antioxidant refers to chain-breaking compound. Broadly antioxidant is any substance, that when present at low concentrations compared with those of an oxidizable substrate significantly delays or inhibits oxidation of that substrate.

Free radicals damage the cell membrane which is composed of lipids and proteins. Their interaction results in the production of the chemical Melondialdehyde which is very harmful, contributing to another important aging process called glycation.

When glucose molecules and other sugars such as fructose attach themselves to proteins, it is called glycation. This results in brownish discoloration of tissues. The binding of sugar to protein causes cross linking of proteins. Cross linked proteins cause more damage by reacting with free radicals and other toxins to create Advanced Glycation Endproducts (AGEs). These AGEs bind to cells at special attachment sites called RAGEs (Receptor for AGEs). These result in the production of several harmful chemicals damaging tissues.

AGEs are found in most tissues in the body and their concentration increases from the age of twenty onward.

However nutrient such as carnosine and other Anti-Aging supplements/drugs can help in breaking this process.

Unfortunately the process of glycation not only affects proteins, but also interferes with DNA. A cross linked DNA molecule is of no use at all. There are drugs being investigated which can actually break this bond between cross linked proteins which are glycated.

When methyl groups are being added to different constituents of the proteins, DNA and other molecules to keep them in good, active condition, it is called methylation. This is necessary for the normal maintenance of tissues and is usually kept at a healthy levels naturally by the body. Methylation of certain parts of the DNA causes permanent switching off of unnecessary genes and saves the body from abnormal DNA division. This means that methylation of those particular sections of DNA blocks any abnormal DNA from being passed onto the future generations of cells.

Any chronic inflammation process affects methylation because the immune system, which is heavily involved in fighting inflammation, gorges itself on methyl groups, leaving nothing for other tissues of the body.

Low methylation is reflected in the increasing levels of homocysteine, which is found in chronic inflammatory processes such as lupus, heart disease and diabetes. Increased intake of methylators reduces the risk of these diseases.

There are scientists who believe that most age related changes in the body are due to chronic inflammation. When there is chronic inflammation, the body tissues are eaten away by toxic chemicals, resulting in dementia, thickening of the arteries, arthritis, diabetes, hormonal imbalance and so on. Taking low dose of anti-inflammatory chemicals such as Aspirin keeps age related inflammation at bay. However, this is not a widely shared opinion. A diet containing nutrients i.e. fish (contains anti-inflammatory oils), fruit and vegetables, particularly berries (which are packed full of antioxidants and inflammation-fighting flavonoids) along with supplements like alpha lipoic acid and co-enzyme Q10 are helpful.

There is little doubt about the important role hormones play in our lives and in aging. The pacemakers of youth, these precious little chemicals keep us young, healthy and vibrant. In general, aging results in imbalance of hormones in the body or one can also ask Does hormonal imbalance cause aging? Hormones such as growth hormone, melatonin and DHEA need to be replaced or reactivated during aging to prevent the body from falling apart. It is also important to make sure that the binding sites of the hormones need to be in good working order. According to Dr. Eric Braverman, proponent of pause theory, every organ in the body ages at a different rate. The classical example of this is the menopause in females and the literature is replete with Hormone Replacement Therapy for the same. It seems prudent to replace the other hormones in physiological limits. Hormone replacement therapy is likely to play a very important role in maintaining health in time to come. It is very important here to make the distinction between the Synthetic hormones and the Bioidentical hormones which is discussed later.

Enhance health through eating a hormonally correct diet

Enrich body with optimum doses of proven antioxidants and nutraceuticals

Improve physical exercise performance, which includes aerobic, anaerobic and flexibility training

Replace hormones to levels to those of 20-30 years old.

The importance of food we eat can be summarized by what Dr. Barry Sears said and I quote: The food you eat is probably the most powerful drug you will encounter. But to use this drug correctly, you have to apply the hormonal rules about the food that haven't changed in the past 40 million years and are unlikely to change anytime soon.

Balancing Insulin and glucagon activity is at the core of eating a hormonally correct diet. The hormonally correct diet contains 30% protein, 50% carbohydrates and 20% fat along with vitamins, minerals and drinking plenty of water which is filtered, mineralized and magnetized. Eating small meals every 4-5 hours and eating the proper ratio of proteins, carbohydrates and fat at each meal or snack can mean a difference between illness and good health.

Eating proper food for one's height, weight and body type and activity level is the foundation for a better quality of life and greater longevity.

Dr. Alex Lief, MD Harvard Medical School has said and I quote: Exercise is the closest thing we have to an anti-aging pill. Regular physical activity has been a way of life for virtually every person who has reached the age of 100 years in sound condition. Exercise is medicine. If you think that smoking is not good, the following statement will enlighten. Not exercising has the equivalent impact on your health as smoking one and one half pack of cigarettes a day.

These include various antioxidants, vitamins and minerals. These include but are not limited to Vitamin A, C, E, mineral selenium, glutathione, superoxide dismutase, Coenzyme Q10, Alpha Lipoic Acid and Carnosine.

First we have to distinguish the synthetic hormones and bioidentical hormones. The former differ in chemical structure from the later which exactly have the same structure as the hormones we have in our body. Hence they can not be patented. These are available as injection, tablets, and creams. They are derived from Yam or Soy. The goal of hormone replacement therapy is to bring them to the level of youth. Again it has to be done after complete evaluation and under the guidance of an Anti-Aging physician.

The future will involve manipulating genes, increasing utilization of stem cells (embryonic and adult) and targeted delivery of nutrients and drugs using nanotechnology.

It is my hope that this will help you begin your educational journey in Anti-Aging Medicine.

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Anti-aging and Longevity Medicine. Medical therapy and …

Longevity An enduring dream of humankind is to find the "Fountain of Youth," a way to the prevention of aging. There are many notions of what causes aging. The idea which seems to tie them all together best is the free radical theory. This notion, put forth by Denham Harmon in the 1950s has it that oxidation liberates molecules with unpaired electrons and that before these unpaired electrons can be taken into the antioxidant systems of the body, damage is done to cell structures, DNA, RNA, and proteins. This is thought to leave the cells of the body in a state of diminished vitality, a kind of damage which is not fully repairable. This includes the vital hormone system.

As far as slowing aging is concerned, perhaps the two most important tools we have are the antioxidant and hormone replacement therapies. Endogenous antioxidants are those which are made by the cells of the body. Exogenous antioxidants are those which are taken in with food or as nutritional supplements. Glutathione is an example of the former. Ascorbate (vitamin C) is an example of the latter. A supplementation program of the precursors of the endogenous antioxidants and of the full range of exogenous antioxidants should, theoretically, slow aging. "Endocrine" glands secrete directly into the blood and circulate immediately throughout the body. "Endo" means inside, thus denoting that these glands place their secretions inside the body, namely into the blood stream. Such a secretion is a "hormone" (derived from a Greek word meaning "to stimulate"). Hormones are the language the body speaks between its various parts, letting the various organs know if they need to speed up or slow down, make more of this or less of that. It is an exquisite biochemical symphony. Blood circulates throughout the body in sixty seconds. Therefore, it takes approximately sixty seconds for a hormone to reach any other part of the body.

The endocrine glands are the following:

The pituitary is listed on top and in capital letters, because it is the so-called "master" endocrine gland. It serves to regulate the other endocrine glands. It produces a variety of "trophic hormones" which tell the other endocrine glands to speed up, work harder. (It also produces HGH or human growth hormone, covered in a separate web page.)

As we age, and the endocrine glands decrease their function, the pituitary begins to whip them like tired horses. This contributes to the development of a state of exhaustion. It is plain and clear to me that normal aging (as distinguished from abnormal aging from poor diet and lack of exercise) is caused by the gradual decline of the endocrine glands with a resulting decrease in circulating hormones. What causes this gradual decline in the endocrine glands probably is the effect of free radical pathology. This, in itself, is something which can be slowed down by proper diet and supplements. Aging cells become more and more resistant to the effects of hormones, and just at that time in life when the body needs a boost in hormone levels, it gets a decrease instead. The hormone secretions of the endocrine glands not only effect the health and well-being of the rest of the body, but they also are dependent on each other to maintain health. Thus, when the thyroid gland takes a nose-dive, and the basal metabolic rate is slowed down, this, in turn, slows down the functioning of all the other endocrine glands. When the parathyroids age, they no longer hold calcium metabolism within the boundaries required for maximal health. When the thymus partially degenerates (which it does by age twenty) the immune system is no longer the lion it once was. When the pancreas puts out less insulin, all the other endocrine glands are denied easy access to glucose, because insulin helps drive glucose into cells. Glucose is an important energy source for the functioning of all the cells of the body.

The adrenal glands are responsible for regulating the body's response to stress through regulation of protein, carbohydrate and mineral metabolism, as well as powering up the immune system in conditions of stress. When the adrenals are exhausted, the other glands are unable to cooperate in reducing the effects of stress, and the body is more susceptible to infections. The adrenals become exhausted through constant exposure to stress from any source. This is an extremely common condition in our society. The testes and adrenals in men and the adrenals alone in women make testosterone, and this hormone is responsible for maintaining aerobic metabolism and preventing the body from resorting to the far less efficient anaerobic metabolism. The ovaries and adrenals in women and the adrenals alone in men make estrogen, which lends softness and pliability to tissues without sacrificing strength. When estrogen production wanes, the connective tissue component of all organs (including the endocrine glands) suffer. The point is: all the endocrine glands work together and depend upon each other, and the failure of one of them affects the rest as well. Endocrine gland failure is inevitable, and it is part of what I call "normal" aging. Warding off abnormal aging is done by proper diet, exercise and sleep. Slowing down normal aging is possible through timely recognition and correction of endocrine failure and there is the rub.

Traditionally, doctors have relied on laboratory tests to diagnose deficiencies. That works well for the under 35 age group. However, after 35 or 40, the amount of hormone needed to maintain a youthful condition goes up progressively. Therefore, if you have a set of symptoms which could be attributed to hormone deficiency, you may go to the doctor, be sent for lab tests and then be told there is nothing wrong with you you are just getting old. Well, that is true, you are getting old, except it is not true that nothing is wrong with you. What is wrong with you is: you are getting old. Doctors say you are just getting old when they cannot correct a problem. Does it make sense to keep saying that when the means are at hand to correct the problem? While it may be true that the endocrine glands are getting old and will not put out as much hormone as needed to keep the rest of the body young, that does not mean we should lie down and learn to live with it. If we can rejuvenate or supplement the endocrine glands, and if that rejuvenation or supplementation is safe and creates an enhanced experience of health and well being, as well as increased longevity, why shouldn't we do it? While it is true that our ancestors had to live with degeneration of the endocrine system, it does not necessarily follow that we should retrace their footsteps. We can now go to the health food store and buy "glandulars," preparations made from animal endocrine organs containing the precursor molecules necessary to power up the various endocrine organs. This works, up to a point, and is especially effective to prevent aging of the endocrine organs and, to some degree, reverse it. When it no longer works, it is now possible to supplement with the actual hormones themselves.

Some of the well-known human hormones which are used in anti-aging medicine are pregnenolone, DHEA, progesterone, androstenedione, estradiol, estrone, estriol. Cholesterol, far from being the toxic substance it is portrayed to be in the popular press is the precursor hormone for all of these. Without cholesterol you would die very quickly. In the oxidized form in the relative absence of antioxidants, especially ascorbate (vitamin C), and in the presence of micro injuries to the vascular wall, cholesterol is one of the items which collects to plug the leak. However, lowering cholesterol too much is more dangerous that allowing it to remain greatly elevated.

Naturally, diet, Aerobic Exercise and Anaerobic Exercise are extremely important in anti-aging medicine.

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Testosterone replacement therapy for older men

Clin Interv Aging. 2007 Dec; 2(4): 561566.

Published online 2007 Dec.

Geriatrics Research, Education, and Clinical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, USA

Despite intensive research on testosterone therapy for older men, important questions remain unanswered. The evidence clearly indicates that many older men display a partial androgen deficiency. In older men, low circulating testosterone is correlated with low muscle strength, with high adiposity, with insulin resistance and with poor cognitive performance. Testosterone replacement in older men has produced benefits, but not consistently so. The inconsistency may arise from differences in the dose and duration of testosterone treatment, as well as selection of the target population. Generally, studies reporting anabolic responses to testosterone have employed higher doses of testosterone for longer treatment periods and have targeted older men whose baseline circulating bioavailable testosterone levels were low. Most studies of testosterone replacement have reported anabolic that are modest compared to what can be achieved with resistance exercise training. However, several strategies currently under evaluation have the potential to produce greater anabolic effects and to do so in a safe manner. At this time, testosterone therapy can not be recommended for the general population of older men. Older men who are hypogonadal are at greater risk for the catabolic effects associated with a number of acute and chronic medical conditions. Future research is likely to reveal benefits of testosterone therapy for some of these special populations. Testosterone therapy produces a number of adverse effects, including worsening of sleep apnea, gynecomastia, polycythemia and elevation of PSA. Efficacy and adverse effects should be assessed frequently throughout the course of therapy.

Keywords: aging, testosterone, hypogonadism, physical function

In young adult men, the hypothalamic-pituitary-gonadal axis regulates the circulating concentration of testosterone. The hypothalamic pulse generator secretes a pulse of gonadotropin releasing hormone (GnRH) approximately every 90 minutes (Reyes-Fuentes and Veldhuis 1993). GnRH is secreted into the hypothalamic-pituitary portal circulation where it stimulates pituitary secretion of luteinizing hormone (LH) (Veldhuis et al 1990) into the systemic circulation. LH reaches the testes and promotes both tonic and episodic Leydig cell secretion of testosterone.

Nearly all of the testosterone circulating in the blood is bound to sex hormone-binding globulin (SHBG) or albumin. The affinity of SHBG for testosterone is about 1,000-fold higher than the affinity of albumin for testosterone (Pardridge et al 1985). Thus the combined free (1%2%) and albumin-bound fractions of testosterone are considered to be bioavailable (Manni et al 1985). Bioavailable testosterone in acts upon multiple target tissues and completes the feedback loop inhibiting GnRH and LH secretion.

The serum testosterone concentration displays both circadian and ultradian rhythms. The circadian rhythm results in peak testosterone serum concentrations during the early morning hours. In contrast, the ultradian rhythm has a cycle whereby the serum testosterone concentration fluctuates approximately every 90 minutes. This ultradian rhythm represents the burst-like secretory pattern of testosterone, which is superimposed on testosterones basal or tonic secretion.

In young adult health, the feedforward (GnRH stimulates LH which stimulates testosterone secretion) and feedback (free or bioavailable testosterone inhibits release of GnRH and LH) components of the hypothalamic-pituitary-gonadal axis maintain the serum total testosterone concentration within a normal range of 4501,000 ng/dL. The mean serum total testosterone concentration for healthy young adults approximates 650 ng/dL.

Unlike female menopause, the decline in testosterone serum concentration in men is gradual, and there is much inter-individual variability. Serum testosterone concentrations decline steadily after young adulthood, and by age of 80 years, the testosterone secretion rate decreases to approximately half that of a younger man (Tenover et al 1987; Mulligan et al 1995).

The decrease in bioavailable-testosterone appears to be greater than the decline in total testosterone with advancing age, due to an age-related increase in SHBG (Rubens et al 1974). The decline in testosterone with aging has been referred to by a variety of names including male menopause, climacteric, viropause, andropause, ADAM (androgen deficiency in aging men), or age-associated hypogonadism. Longitudinal studies confirm a decline in testosterone with aging, as has been reported earlier in cross-sectional studies (Morley et al 1997; Feldman et al 2002).

With age, changes that contribute to hypogonadism occur in both the hypothalamus and testes. The rise in LH following a decrease in testosterone is considerably blunted with age (Korenman et al 1990; Veldhuis et al 2001). This is likely due to failure of the hypothalamus to generate an appropriate burst of GnRH secretion (Veldhuis et al 1994; Mulligan et al 1999). The specific mechanism may be an age-related increased sensitivity of the hypothalamic-pituitary unit to the negative feedback effect of testosterone (Winters et al 1984). In older men, the decline in circulating testosterone also correlates with changes in the testes, specifically a decline in Leydig cell number (Neaves et al 1984), development of vacuolizations and lipofuscin within the Leydig cells, and decreased Leydig cell secretion of testosterone in response to provocative stimulation with human chorionic gonadotrophin (Harman and Tsitouras 1980).

The decline in bioavailable testosterone may be at least partially responsible for the decreased muscle mass, osteoporosis, mood disturbances, and frailty seen in older men (Nunez 1982).

The criteria for low testosterone are the same regardless of age. Symptomatic men with a total serum testosterone concentration less that 200 ng/dL are definitely hypogonadal, while those with a concentration between 200 and 300 ng/dL are probably hypogonadal. The prevalence of hypogonadism increases with advancing age; the odds ratio of hypogonadism is greater with each 10-year increase in age. Longitudinal studies in specific geographic areas of the United States and some small cross-sectional studies have demonstrated a decline in testosterone occurring as early as age 30, but usually testosterone levels remain within normal limits until men reach age 60 (Belanger et al 1994; Morley et al 1997). The prevalence of low serum total testosterone among men aged 45 years or older has been estimated to be 39% (Mulligan et al 2006). The prevalence of symptomatic hypogonadism is considerably lower, estimated as 6%12% in a group of men aged 4060 years in the report of the Massachusetts Male Aging Study (Araujo et al 2004).

Low serum testosterone concentration in older men is associated with depression (Shores et al 2005). However, most trials of testosterone replacement have not shown improvement in depression. Two small studies in younger hypogonadal men did show short term improvement in depression with testosterone supplementation, but this effect has not been reproduced in older men (Pope et al 2003). The age of onset of depression may also be a factor in response to testosterone. Perry et al (2002) reported that 6 weeks of testosterone treatment improved depression scores in men who had onset of depression after the age of 45 years, but not in men whose depression started at a younger age.

Higher bioavailable testosterone levels are associated with better performance in cognitive tests (Barett-Connor et al 2004). Short-term trials in healthy eugonadal older men have shown improvement in verbal and spatial memory (Cherrier et al 2001; Gray et al 2005). However, longer trials have produced mixed results. Haren et al (2005) reported no improvement in cognition or memory. In a recent study by Cherrier et al (2006), older men were treated for 6 weeks with testosterone at doses of 50, 100 or 300 mg/week. Interestingly, improvements in verbal and spatial memory were observed only with the intermediate dose.

Testosterone produces substantial anabolic effects in young and middle-aged hypogonadal men (Bhasin et al 2001). In contrast, the anabolic effects of testosterone replacement therapy in older men have been harder to demonstrate. Among the many published trials of testosterone in older men, some report strength gains and some do not. Only a few report strength gains that can be considered substantial in comparison to the benefits of resistance exercise training. In most cases, the studies reporting significant strength gains were performed in hypogonadal subjects and employed a higher dose of testosterone, for a longer duration.

In a recent report, Nair et al (2006) describe treating a group of hypogonadal men for 24 months with a transdermal testosterone at a dose of 35 mg/week and finding no increase in strength. However, 35 mg/week is less than a replacement dose and resulted in only a 30% increase in the circulating testosterone concentration. Studies by Brill et al (2002), Clague et al (1999), Kenny et al (2001), and Snyder et al (1999) also report small increases in strength. Brill et al treated older men for 1 month with 5 mg testosterone/day by patch and found an improvement in stair climb time, but no increase in strength. Clague et al treated men aged 60 or more with total T of 400 ng/dL or less were treated with 200 mg testosterone enanthate every two weeks by i.m. injection for 3 months and found no significant increase in strength. Kenny et al (2001) treated hypogonadal and low-normal older men with 5 mg testosterone/day by patch for 1 year and found a 38% increase in strength with testosterone, but surprisingly also a 27% increase with placebo, with no significant difference between the two groups. Snyder et al (1999) treated older hypogonadal and eugonadal men for 36 months with 6 mg testosterone/day by patch and found no increase in strength.

Several investigators have reported that testosterone caused moderate increases in strength; increases that are significant, but are still below than what can be obtained through resistance exercise training. Wang et al (2000) treated younger and older men (aged 1968) with total T of 300 ng/dL or less with a titrated dose of testosterone gel (equivalent of 5 to 10 mg per day) for 6 months found that the higher dose caused, a reduction in negative moods, a sizable increase in hematocrit (from 42 to 47), and modest increases in arm and leg strength. Sullivan et al (2005) conducted a 3-month study of low- or high-intensity resistance exercise training in men aged 65 or more, who were not hypogonadal (total T = 480 ng/dL or less). Some subjects also received a weekly i.m. injection of 100 mg testosterone enanthate. The addition of testosterone produced a trend toward greater increases overall, but the effect of testosterone appears to be substantial in the low-intensity training group. Considering that few men in the community will perform high-intensity training on their own, these results may indicate usefulness for testosterone therapy.

Three studies have reported substantial strength gains following testosterone treatment and all have employed doses of testosterone that are somewhat higher than replacement doses. Ferrando et al (2002) treated older hypogonadal and eugonadal men for 6 months with a biweekly injection of testosterone that was titrated to raises circulating testosterone into the normal range and resulted in an approximated doubling of circulating testosterone (from 300 to 600 ng/dL). Significant strength increases were observed, including a 15 kg increase in leg extension 1-RM strength. Page et al (2005) treated a group of older, hypogonadal men for 36 months with biweekly i.m. injections of 200 mg testosterone enanthate and found significant improvements in hand grip strength. However, the study that best demonstrates the dose dependence is that of Bhasin et al (2005). Both older and younger men were first made hypogonadal with luprolide and then treated for 5 months with testosterone enanthate at doses ranging from 25 mg to 600 mg/week. Higher doses of testosterone produced large increases in strength, including an increase of 50 kg in leg press 1-RM strength in older men receiving a dose of 300 mg/week. The doses of 300 and 600 mg/week produced a high incidence of adverse effects and a dose of 125 mg/week was considered to be the best trade-off of beneficial and adverse effects.

The dose of testosterone also appears to be critical in determining whether increases in bone mineral density are observed. Snyder et al (1999) treated older hypogonadal and eugonadal men for 36 months with 6 mg testosterone/day by patch and found that bone mineral density did not increase overall, but did do so in the group with the lowest pretreatment testosterone levels. However, Amory et al (2004) treated older hypogonadal men for 36 months with biweekly i.m. injections of 200 mg testosterone enanthate and obtained substantial increases in bone mineral density, 3%4% in the hip and a remarkable 10% in the lumbar spine.

The lower rate of heart disease in women has historically been attributed to the cardioprotective effects of estrogen. Presently, this position is being reexamined. The cardioprotective effects of estrogen have come into some question and there is emerging evidence that testosterone may have cardioprotective effects of its own. Swartz and Young (1987) have shown that older men with a low circulating testosterone, a higher fraction have previously suffered a myocardial infarction. Testosterone supplementation in hypogonadal men improves exercise tolerance and decreases exercise-associated ischemia in elderly patients with coronary artery disease and low (Malkin et al 2004) or low-normal (English et al 2000) testosterone. This protection may be secondary to a vasodilatory effect and/or higher pain threshold. The vasodilatory effect has been confirmed in animal models (English et al 2002). The beneficial effects are seen with both acute (Rosano et al 1999) and chronic (English et al 2000, 2002) testosterone administration, and also with low (Malkin et al 2004) and high (Rosano et al 1999) dose supplementation. However, none of these studies was long enough to show an effect on cardiovascular mortality.

Although there has been concern that testosterone therapy might adversely affect serum cholesterol and lipids, this concern has not been bourn out in controlled studies. Wang et al (2000) reported that treating hypogonadal men with testosterone gel (equivalent of 510 mg per day) for 6 months did not produce significant changes in LDL- or HDL-cholesterol. Whitsel et al (2001) performed a meta analysis of 19 studies involving administration of testosterone esters to older hypogonadal men and found that, on the whole, testosterone produces small, and probably offsetting, decreases in both HDL and LDL. An additional cardiac benefit of testosterone may be seen in the findings of Malkin et al (2004), who found that testosterone reduced circulating levels of tumor necrosis factor alpha and interleukin-1 beta, inflammatory cytokines that are elevated in heart failure.

Risks associated with testosterone replacement in elderly men include fluid retention, gynecomastia, worsening of sleep apnea, polycythemia and acceleration of benign or malignant prostatic disease (Matsumoto 2002). A high incidence of adverse effects was observed by Bhasin et al (2005) in treating older men with the very high doses of 300 and 600 mg/week.

Among these risks, the potential effects of testosterone on the prostate are of the greatest concern. These concerns stem from the known action of testosterone in accelerating active prostate cancer and from the high prevalence of early-stage prostate cancer in elderly men. While approximately 10% of men will develop clinically manifest prostate cancer in their lifetime and 3% will die of the disease, autopsy data show that 42% of men over the age of 60 have early-stage prostate cancer (Mikuz 1997). Clinical trials to date are not large enough or long enough to determine the potential effects of testosterone treatment on prostate cancer. Although Zitzmann et al (2003) have shown that replacement and slightly higher doses of testosterone produce a predictable and moderate degree of prostate enlargement, existing data do not indicate that testosterone promotes prostate cancer. Hajjar et al (1997) treated elderly men with a replacement dose of testosterone and found no increase in prostate cancer during a 2-year follow-up. Agarwal and Oefelein (2005) administered testosterone for 19 months to hypogonadal patients with a history of prostate cancer and prostatectomy, but whose recent PSA levels were low. Treatment significantly elevated circulating testosterone and improved quality of life without elevating PSA.

Patients should be evaluated one month after initiation of treatment and the dose should be increased if symptoms of hypogonadism have not improved. Rhoden and Morgentaler (2004) have reviewed the adverse effects and recommend the following monitoring. Safety monitoring should include sleep apnea, voiding symptoms, serum testosterone, PSA and hemoglobin or hematocrit and should be performed several times during the first year and yearly thereafter.

In response to concerns over the efficacy and risks of hormonal replacement in the elderly, the NIH commissioned an assessment by the Institute of Medicine (IOM). The IOM report states that there is insufficient evidence to conclude that testosterone treatment in older men has well established benefits. In addition, the IOM recommended that small and medium-sized trials be conducted to assess the efficacy of testosterone for treating muscle weakness, osteoporosis, sexual dysfunction, cognitive impairment and depression (Liverman and Blazer 2004). The IOM does not recommend prevention trials or trials for all hypogonadal older men. While we agree with these recommendations, at least two other avenues of exploration deserve attention.

First, while replacement doses of testosterone do not consistently produce substantial increases in strength, Page et al (2005) and Bhasin et al (2005) have shown that higher doses of testosterone do produce such increases. Higher doses of testosterone also produce more adverse effects, especially prostate effects. Strength, especially lower body strength, remains an important facto limiting the independence of older people. Currently, alternative strategies are being developed, aimed at stimulating the androgen receptor more powerfully, without producing added adverse effects. One such strategy is to administer a higher dose of testosterone with the addition of a 5-alpha reductase inhibitor to prevent the prostate symptoms. Another strategy is the use of selective androgen receptor modulators (SARMs), currently under development at several pharmaceutical firms.

A second avenue where more research is needed is testosterone therapy for special populations of men who are at risk for development of catabolic states and muscle wasting. Testosterone might be used to prevent disuse muscle atrophy following knee or hip replacement. A study by Amory et al (2002) suggests that treating men with testosterone before knee replacement surgery improved functional independence after. While these results were not dramatic, one limitation of the study is that testosterone therapy did not continue after surgery, ie, during the period of muscle atrophy. In addition, hypogonadism and muscle wasting are associated with a number of conditions that are more common in older men including COPD (Debigare et al 2003), coronary artery disease (Rosano et al 2006), glucocorticoid therapy (Salehian and Kejriwal 1999), and acute ischemic stoke (Jeppesen et al 1996). It is likely that in some cases, testosterone therapy may prevent catabolic/muscle wasting syndromes associated with these conditions.

In conclusion, while it is true that most studies of testosterone replacement in older men have not produced substantial increases in strength, testosterone therapy continues to hold promise for older men. Testosterone may be of greater use in special populations who are at risk for development of a catabolic state (eg, patients recovering from a long period of bed rest or joint replacement). In addition, there is promise that strategies will be developed to stimulate the testosterone pathway more robustly and to do so in a safe manner. If so, there may be indication for use of such therapy in a broader segment of the population of older men. In the meantime, truly hypogonadal men (those who are symptomatic men and have a serum testosterone concentration below 200 ng/dL) who have no contraindications to testosterone replacement therapy (eg, prostate cancer) may benefit from testosterone replacement regardless of whether they are 30 or 80 years of age.

Articles from Clinical Interventions in Aging are provided here courtesy of Dove Press

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Paleo diet science and research – Robb Wolf

One of the most common questions we receive is what research is there on the Paleo Diet? Thats a great question and Id recommend thoroughly reading ALL of themateriallisted on this page if you have questions or curiosity about the Paleo Diet.

Prof. Loren Cordain has a remarkable number of peer reviewed papers on his site.

Prof. Staffan Lindeberg has conducted research on both free living hunter gatherers and in clinical settings.

The Protein Debate is a project we funded in which Prof. Loren Cordain debated China Study author T. Colin Campbell about the role of protein in degenerative disease.

We talk a lot about nutrition on this site but exercise is a key component of a healthylifestyle. Prof. Frank Booths paper is a phenomenal exploration of the importance of exercise and health.

Here is a list of some of the other studies that have been done in regards to a Paleo Diet:

Paleolithic nutrition for metabolic syndrome: systematic review and meta-analysis

Metabolic and physiologic effects from consuming a hunter-gatherer (Paleolithic)-type diet in type 2 diabetes.

Evolution of the diet from the paleolithic to today: progress or regress?

Evaluation of biological and clinical potential of paleolithic diet

Effects of a short-term intervention with a paleolithic diet in healthy volunteers

Comparison with ancestral diets suggests dense acellular carbohydrates promote an inflammatory microbiota, and may be the primary dietary cause of leptin resistance and obesity.

Evaluation of biological and clinical potential of paleolithic diet

Effects of a short-term intervention with a paleolithic diet in healthy volunteers

Long-term effects of a Palaeolithic-type diet in obese postmenopausal women: a 2-year randomized trial

If you want to find more, PUBMED is one of the largest repositories of humanlearningin existence. Put in asearchterm like Paleo Diet or Hunter Gatherer and get ready to learn! And check out Scientific Research 101 if you need a tutorial on how to read research studies.

Paleodiet.com is full of paleo diet goodness.

I hear thisGooglething might catch on.

Calcium

Acid Basebalance

Fatty acids(including omega 3s and 6s) My rough recommendation on fish oil supplementation is 2-4g per day.

What about thefructose/glucosecontent of fruits?

What aboutKetosis? Dr. Mike Eades has a fantastic blog and here is an amazing primer on Ketosis:Metabolism & Ketosis. What about ketosis and exercise? Here is a great piece detailing both anthropological data and modern laboratory data on the subject:Ketogenic diets and physical performance. The bottom line? No glycogen, no glycolytic activity!

Are beansgood for you?No.

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Paleo diet science and research - Robb Wolf

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BodyLogicMD – Hormone Replacement Therapy for Men

Hormone therapy programs aren't only for women. Men experience a more gradual loss of hormones, mainly testosterone. The result is andropause, known as the "male menopause." Andropause can make daily life feel like an uphill battle, and because men are living longer, more active lives they are seeking and finding relief from the serious symptoms of hormone imbalance with bioidentical hormone replacement therapy for men.

The signs of andropause and related hormonal issues include:

This personalized, medically supervised program includes natural HRT for men, as well as customized fitness and nutrition programs for millions of men suffering from hormonal imbalance. These expert bioidentical hormone doctors provide a natural treatment for the symptoms of andropause, helping men regain their health and confidence.

Hormonal imbalances in men are at the root of many chronic health problems and can increase the risk of serious disease. BodyLogicMD affiliated physicians have developed customized hormone replacement therapy for men that has proven successful in supporting men's health and a healthy hormonal balance.

Individual male hormone replacement treatment programs includes:

To determine your hormonal needs, BodyLogicMD affiliated physicians thoroughly evaluate your symptoms using state-of-the-art diagnostic tests, such as, saliva, urine and/or blood tests to determine your hormone levels and your unique bioidentical hormonal needs. After starting bioidentical hormone therapy, your physician will monitor and re-evaluate your hormone levels, meeting with you, to insure that they are maintained at their optimum balance.

Read about Bioidentical Hormones For Women

CONTACT A PHYSICIAN

CLICK HERE

HORMONE BALANCE QUIZ Take it now!

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Low-T (Low Testosterone) Quiz on MedicineNet

Q:Testosterone is a chemical found only in men.

The correct answer is: False

Explanation:

Testosterone is a steroid hormone which is made in the testes in males and in the ovaries in women (a minimal amount is also made in the adrenal glands).

The correct answer is: False

Explanation:

Menopause itself does not seem to play a role in a reduction of testosterone levels in women. With advancing age, in both men and women, the body produces decreasing amounts of testosterone over time.

The correct answer is: Men

Explanation:

Testosterone is the most important hormone in men. While it helps to maintain sex drive, sperm production, pubic hair and body hair, testosterone is also responsible for maintaining muscles and bones.

When testosterone production is low in men, sexual dysfunction is a common complaint; but other nonspecific symptoms such as depression, mood changes, weight gain, or fatigue, have been reported.

The correct answer is: DAll of the above

Explanation:

An upsurge in media attention regarding the so-called "male menopause" has left many men rushing to their doctor to treat symptoms they believe may be related to low levels of testosterone. The thought behind the concept of male menopause is that the decline in testosterone levels that occurs as men age may produce a characteristic and potentially treatable set of symptoms. Male menopause is also commonly referred to as low-T, andropause, or its medical name, late-onset hypogonadism.

The correct answer is: DAll of the above

Explanation:

Low levels of testosterone in men can affect a man in the following ways: - Loss of sexual interest and function - Erection problems - Increased breast size - Hot flashes - Problems with memory and concentration - Mood problems such as irritability and depression - Smaller and softer testicles - Loss of muscle strength and weakened bones

Symptoms of low testosterone levels in women include: - Hot flashes - Irritability - Loss of sexual desire - Sleep disturbances - Loss of muscle mass - Decreased bone density (osteoporosis)

The correct answer is: BThe brain

Explanation:

Testosterone production is regulated by hormones released from the brain. The hypothalamus and pituitary gland, located in the brain, produce hormonal signals that ultimately result in the production of testosterone. These hormones travel through the bloodstream to activate the sex organs in both men and women.

The correct answer is: False

Explanation:

In men, low testosterone levels in the body can be supplemented by hormone replacement with testosterone. Testosterone replacement therapy can be prescribed as an intramuscular injection usually given on a biweekly basis; as a patch or gel placed on the skin, or as putty that is applied to the gums of the mouth. Each of the treatments has its risks and benefits. The decision as to which form of testosterone to use depends upon the clinical situation. Discussions between the patient and health care professional often helps decide which medication to use.

In the United States there are currently no preparations that are FDA approved for testosterone replacement for women.

The correct answer is: CDiabetes

Explanation:

Men with diabetes are more likely to have low testosterone. Moreover, men with low testosterone are more likely to develop diabetes later. Testosterone helps the body's tissues take up more blood sugar in response to insulin. Men with low testosterone more often have insulin resistance.

Note: Scientists aren't sure whether diabetes causes low testosterone, or the other way around. Still, a link between diabetes and low testosterone is well established.

The correct answer is: BObese

Explanation:

Research has shown that nearly 40% of obese men over age 45 have a low testosterone blood levels. Men with very low testosterone also are more likely to become obese. Losing weight through exercise can increase testosterone levels. Testosterone supplements in men with low testosterone also can slightly reduce obesity.

The correct answer is: False

Explanation:

For a reasonably healthy man, having no interest in sex is not normal. As a man ages, it is natural for him to have less interest in sex than when he was younger. A gradual decrease of testosterone is normal as a man ages, but it is not normal for a healthy, older man, to have no interest in sex.

A man of any age who has lost interest in sex should have a frank conversation with a doctor.

The correct answer is: False

Explanation:

Many people with low testosterone have no symptoms. Only a blood test can determine a person's testosterone levels. The Endocrine Society considers 300 to 1,200 nanograms per deciliter (ng/dL) normal, and that less than 300 is low. Doctors usually use a blood test and a number of symptoms to make a diagnosis and to determine whether treatment is needed.

The correct answer is: False

Explanation:

From puberty, when a boy starts to grow a beard and pubic hair, testosterone affects hair growth in men. But it doesn't affect growth on all parts of the body the same way. Low testosterone can cause you to lose body or facial hair, but it doesn't cause male pattern baldness. Genetics have more to do with male pattern baldness.

The correct answer is: CAlcoholism

Explanation:

Alcohol is directly toxic to the testicles where testosterone is produced, and it seems to affect the release of other hormones related to men's sexual function and fertility. Shrunken testicles are a common sign of low testosterone in alcoholic men with liver disease, as well as lower libido and sexual potency. Enlarged breasts are common in heavy drinkers because alcohol may help convert testosterone into the female hormone estrogen.

The correct answer is: True

Explanation:

Up to 9 out of 10 men who have symptoms of low testosterone may not seek treatment. They may attribute their symptoms to other conditions or think their symptoms are a normal part of aging. Guys, if you have symptoms and believe they are having an impact on your quality of life and well-being, talk to your doctor.

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Reviewed by Charles Patrick Davis, MD, PhD, on October 1, 2012

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Sources:

MedicineNet. Low Testosterone (Low T). <http://www.medicinenet.com/low_testosterone/article.htm>

womenshealth.gov. Men's Health. <http://www.womenshealth.gov/mens-health/sexual-health-for-men/sexual-problems.cfm#low>

MedicineNet. Male Menopause: Fact or Fiction? <http://www.medicinenet.com/script/main/art.asp?articlekey=119561>

WebMD. Low Testosterone and Your Health. <http://men.webmd.com/what-low-testosterone-can-mean-your-health>

WebMD. Quiz: The Truth About Testosterone. <http://www.webmd.com/sex-relationships/low-testosterone-8/rm-quiz-truth-testosterone>

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Low-T (Low Testosterone) Quiz on MedicineNet

Recommendation and review posted by Alexandra Lee Anderson

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Low T (Low Testosterone)

Don't Let Low Testosterone (LowT) Get You Down. Fight Back, Intelligently!

Testosterone levels start declining around the age of 30 by 1 to 2 % per year. By the age of 45, the average mans testosterone levels have started dropping precipitously. By the age of 80, most men have less than 20% of the testosterone they had when they were in their 30s. This process of declining testosterone is often referred to as Andropause (or male menopause), and because it takes place gradually over decades, the symptoms of Low T often go unnoticed for a long period of time.

Not only does normal aging cause a decrease in testosterone levels, there are quite a number of other causes of Low T that affect many men. Among these are: stress and various medications. In addition, the following can also cause Low T: alcoholism, cirrhosis of the liver, cancer treatments such as chemotherapy and radiation, pituitary dysfunction, chronic kidney failure, too much iron, testicular damage or infection, AIDS and other chronic diseases.

Another way to increase your testosterone levels is to do it naturally. Thousands of men (especially in Asia) use a rain forest herb that naturally causes their body to produce its own testosterone. Because testosterone is produced by the body rather than coming from an outside source, there are no negative side effects using this method. It has also been found to be a very cost-effective approach to resolving the problem of Low T.

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Low T (Low Testosterone)

Recommendation and review posted by Alexandra Lee Anderson

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