Category Archives: Lifestyle and Aging

Arginine for Inflammation and Erectile Dysfunction

For men, arginine may pose as almost a miracle amino acid for inflammation and erectile dysfunction, but one should be wary that arginine combined with other amino acids, protein, and lifestyle changes are more likely the answer.

Arginine, has been getting a lot of attention for it can be an amazing anti-aging amino acid. It also may be useful for graying hair, loss of hair, heart disease, preventing heart failure, and possibly inflammation.

This is where pieces of the arginine amino acid puzzle starts to thicken.  Inflammation and erectile dysfunction are two problems often linked together as exemplified by the article “Reduction of Inflammation Improves Endothelial Function and ED” whereby “minimizing infection and inflammation throughout the body, including avoiding fat accumulation, should improve both vascular and erectile health.”

The link may be attributed to arginine being needed by the body to make nitric oxide.

Because nitric oxide is crucial for maintaining healthy blood pressure, it also helps prevent atherosclerosis, and plays a role in modulating immune system function. In addition, nitric oxide regulates several processes in the body, including fat and glucose metabolism.

Researchers found that inhibiting nitric oxide production was associated with fat gain while stimulating nitric oxide secretion was correlated with enhanced lipolysis, or fat breakdown, according to research published in the September 2006 issue of the Journal of Nutritional Biochemistry.

The best part about nitric oxide is that it is readily available on a sunny day.

Is Nitric Oxide the Cure for Inflammation and ED?

There is some strong evidence that indicates nitric oxide may help both inflammation and ED. In the study, “Role of Nitric Oxide in Inflammatory Diseases” they concluded NO (nitric oxide) inhibitors “represent important therapeutic advance in the management of inflammatory diseases”.

Additionally, the amino acid L-arginine stimulates nitric oxide, which releases “growth hormone, insulin, and other substances in the body.” Prescription drugs also may contribute to maintain the nitric oxide in the body, which can also help prevent erectile dysfunction.

In conclusion, when it comes to adults, and particularly men of industrialized countries, the issue may not be so much about consuming enough protein and amino acids, the concern might be to see the bigger picture and rooting out the problem of inflammation and erectile dysfunction, instead of just ‘curing’ this challenge with a quick fix. Certainly stress is one factor, lack of sleep another, but also being mindful of our diets and exercise.

References:

http://www.medscape.com/viewarticle/761122_18

http://articles.mercola.com/sites/articles/archive/2013/07/15/sun-exposure.aspx

http://www.livestrong.com/article/233939-l-arginine-weight-loss/

http://www.ncbi.nlm.nih.gov/pubmed/18236016

http://www.webmd.com/vitamins-supplements/ingredientmono-875-L-ARGININE.aspx?activeIngredientId=875&activeIngredientName=L-ARGININE

Amino Acids Among Anti-Aging Bio-Molecules

Amino acids are among a number of specific types of bio-molecules that help restrict the aging process. Antiaging creams and lotions and supplements are only a few ways to deal with wrinkles and skin issues from a topical advantage, but what about the rest of the body? Anti-aging mechanisms, healing and immunity, skin (our largest organ), and other biological processes require an internal process at the cellular level for really slowing the aging process.

A review by P Dabhade and S Kotwal from the University Department of Biochemistry, RTM Nagpur University, in India wrote a publication titled: Tackling the aging process with bio-molecules: a possible role for caloric restriction, food-derived nutrients, vitamins, amino acids, peptides, and minerals.

The researchers said that “Aging is a multifactorial process leading to general deterioration in many tissues and organs, accompanied by an increased incidence and severity of a wide variety of chronic, incurable, and often fatal diseases” and that these therapies “include potential dietary interventions, adherence to nutrition, hormonal and cell-based therapies, genetic manipulations, and anti-aging supplements or nutrients.” Amino acids are among them.

Amino acids help with anti-aging at the cellular level

True healing comes from within, and the anti-aging process is no different. The body regenerates at the cellular level, so aiding the body in fundamental ways is crucial to keeping the body youthful. This can mean environmental changes we can control, like one’s diet, includes eating nutrient-rich foods (many people also claim their skin was the most obvious change they noticed when they ate a raw vegan diet because the skin hydrates from underneath).

Among the supplements and nutrients that are listed for anti-aging processes includes, vitamins, minerals, peptides, as well as amino acids. Protein foods like meats can provide all 22 amino acids since aminos are the building blocks of protein. Eating whey protein and eggs provide essential amino acids to the body, but extending the lifespan can get more detailed. The researchers who published the review named above focused mainly on these strategies for slowing down the aging process: caloric restriction, good food, and nutritional supplements, among which include amino acids.

Amino acids that are specifically good for anti-aging

Some of the amino acids below serve specific functions in the body:

Taurine helps repair muscle tissue, which tends to wane in the elderly

Creatine is produced by L-arginine and methionine, which come from carnitine, and help produce healthy skin.

L-arginine also helps reduce inflammation and erectile dysfunction (ED), and serves as a metabolism booster.

L-carnitine and carnosine help support cardiovascular health– carnitine helps with skin health, weight management, and energy, plus reduces peripheral vascular disease symptoms and heart angina, while carnosine lowers cholesterol and also reduces the risk of atherosclerosis.

L-glutamine stores sugar as glycogen instead of fat in the body, and is important for skin health.

Cysteine is a powerful detoxifier and required along with glutamine and glycine in order to make glutathione. The Washington Times called the amino acid glutathione an anti-aging machine!

Aging is progressive, irreversible, and a universal human phenomenon. Utilizing amino acids and other supplements may help protect against damage to molecules such as proteins, DNA, lipids, organs, and our cells protects against diseases like heart disease, cancer, Alzheimer’s disease, arthritis, and osteoporosis.

Taking amino acids, among other supplements, and eating a healthy diet aids cellular mechanisms and may help you live longer. Please check with your doctor before taking any supplements.

References:

http://www.ncbi.nlm.nih.gov/pubmed/23451844

http://www.studymode.com/essays/Submission-619316.html

http://aminoacidinformation.com/?s=anti-aging

Amino Acids and Vitamins Improved Health in Elderly

As we age, it is generally believed our immune system deteriorates. It is considered a fact of life. Japanese researchers did a study to investigate the effects of supplementing amino acids and vitamins for both unhealthy and healthier older people for both inpatients and outpatients.

From the article, “Amino acid and vitamin supplementation improved health conditions in elderly participants”, Japanese researchers studied one bedridden inpatient group and one outpatient group.

Daily, a mixture of the amino acids containing leucine (1200 mg/day), glutamine (600 mg/day), and arginine (500 mg/day), plus 11 kinds of vitamins were administrated for 8 weeks. In both groups, general blood biomarkers such as C-reactive protein levels, white blood cell count, and natural killer (NK) cell activity were measured.

The study involved thirteen bedridden inpatients (7 males, 6 females; mean age, 81.8 ± 8 years) and eleven outpatients (7 males, 4 females; mean age, 74 ± 12 years) from the Sansei Hospital (Hyogo Prefecture, Japan).

These same amino acid and vitamins were administered to the inpatients as the outpatients with water twice daily, immediately after dinner and before sleeping.

Results from clinical study on Amino Acids and Vitamins

The researchers found that supplementation of the three amino acids arginine, glutamine, and leucine, and 11 kinds of vitamins had beneficial effects on the health of older people in poor health. The aging process in humans results in a condition called sarcopenia, which involves decreased skeletal muscle mass and function which is associated with metabolic diseases such as obesity and type 2 diabetes.

In this study, immune parameters were also evaluated. Of these, NK cell activity, an index of innate immunity, increased in both outpatients and inpatients. In the immune system, NK cell activity is thought to be one of the important indices for monitoring immunity because innate immunity is the first line of defense against infections. For those inpatients who were administered amino acids, their condition was stable due to increased NK cell activity.

To conclude, this study suggested that “dietary supplementation with the amino acids arginine (500 mg/day), glutamine (600 mg/day), leucine (1200 mg/day), and 11 kinds of vitamins for the elderly in poor health increased NK cell activity, irregardless of the presence of a primary disease and the amount of the daily nutrient intake.”

It was also observed that supplementation with more than 1 g/day of vitamin C enhanced immunity in healthy adults. In addition, vitamin E fostered the immunity for both unhealthy subjects (750 mg/day) and in healthy elderly subjects (800 mg/day).

References:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3303480/

http://www.nia.nih.gov/health/publication/biology-aging/immune-system-can-your-immune-system-still-defend-you-you-age

The Youthful Old: Amino Acids are Among Methods Used for Anti-Aging

As the older generations get older they turn to what works for helping reverse the aging process. As we age our bodies’ cells stop regenerating at the same rate they used do, and things slowly start deteriorating. Entropy takes a hold, and wrinkles appear, skin thins and loses elasticity, and our bodies do not work quite as efficiently as they used to. Tonics and television ads announcing the next “fountain of youth” seem to have the next best thing, but what does science actually test in their studies, and what actually works? Evidently amino acids, among a list of other things, are among the many tools and methods people can use to help reduce the signs of aging and bring some vitality and life back to an old soul.

Amino acids are the building blocks of proteins. They perform functions in our bodies that are necessary at just about every level, from tissues and organs, skin and hair, muscles and the immune system. All 22 amino acids come from protein foods, but some are actually created by our bodies (non-essential amino acids) while others must be gotten from food (essential amino acids). This would include meats, fish, eggs, dairy, nuts, seeds, and beans.

Anti-aging with bio-molecules and amino acids

According to P Dabhade and S Kotwall, the way to help slow down or reverse the aging process starts with the process of bio-molecues. To help avoid incurable or chronic or even fatal diseases, slow the aging process, as well as improving quality of life, the researchers who reviewed some bio-molecules that are part of anti-aging therapies. Some of the interventions were dietary and included:

Adherence to nutrition
Anti-aging supplements/nutrients (e.g., amino acids)
Genetic manipulations
Hormonal therapies
Cell-based therapies

Skin treatments contain amino acids

Researchers M Ooe, T Seki, et al., did a comparative evaluation of different treatments for wrinkles. Since noninvasive cosmetic surgery and aesthetics were common, but nothing existed for how to treat the wrinkles themselves, they compared four wrinkle treatment methods, including amino acids:

YAG laser treatment
CT-atRA external application
Intense pulsed light (IPL) therapy
Nutritional therapy with amino acid supplements

The results were that all four procedures, which were minimally invasive, had “demonstrated statistically significant improvement in the degree of wrinkle. As for the subjective assessment of VAS, all four treatments demonstrated equivalent satisfaction.” The bottom line is that amino acids may actually help get rid of wrinkles rather than just covering them up topically.

Dr. Oz on which amino acids are anti-aging

So of these methods for anti-aging, which amino acids actually can help with the process? Well, Dr. Oz says that there are five ways to supercharge your body in five days, and amino acids are one of them.

Says Dr. Oz, and HGH levels (Human Growth Hormone, which also may help the antiaging effect) mentioned in a study, that “a special blend of four amino acids has the potential to spike HGH levels by more than 600%. To boost your HGH levels naturally, try taking this supplement that researchers have deemed the most powerful anti-aging amino acid combination.”

These four naturally anti-aging amino acids include:

Arginine (give you energy, regulates blood pressure, keeps heart from working as hard, may help lower body fat)

Glycine (supports muscles, helps you store energy, helps you sleep)

Lysine (helps your body make energy from fatty foods)

Ornithine (gives you energy by removing toxins out of your body)

Dr. Oz recommends an amino acid complex that has a combination of at least 2000 mg of these amino acids.

If you have any questions regarding amino acid supplements please talk with your physician or naturopath.

References:

http://www.ncbi.nlm.nih.gov/pubmed/23451844

http://www.ncbi.nlm.nih.gov/pubmed/23397058

http://www.doctoroz.com/videos/supercharge-your-body-5-ways-5-days?page=4

Part 2: Amino Acids for Men – Virility and Libido (Ornithine)

Continued from Part 1: Amino Acids for Men – Virility and Libido (Arginine), we discussed how the amino acid arginine has no side effects but may help with erectile dysfunction (ED) and potency in men. Now I will discuss the amino acid ornithine and why it is a perfect match as a supplement to go with arginine.

Ornithine and arginine are both considered excellent amino acids for men.

Amino acids for men – ornithine

First of all, let me say that, like arginine, ornithine is side effect-free. Plus ornithine is “reduced to arginine in the body,” says Amino Acid Studies, “but this occurs very slowly, so that its effects last a long time.” There is something about combining these two aminos that sets up the body for overall regeneration, which helps vitality in a big way (no pun intended).

Erectile dysfunction (ED) and erectile capabilities have shown positive support in men who take ornithine, especially when it is taken in conjunction with arginine. These improvements can lead to a boost in the self-confidence in men’s sexuality and drive.

Normally the body can produce amino acids for men—like arginine and ornithine—by itself or can be gotten through food (particularly meats like fish, chicken, beef, turkey, pork, or even eggs), but sometimes the body, left to its own devices or for one reason or another (age, genetics, diet, etc.), does not make sufficient quantities of ornithine or arginine.

If the body cannot produce these amino acids for men by itself, then one has to look into the reasons why this is happening. Typically one can take amino acid supplements, but reasons for this could include stress, or even illness. Illness is more obvious as a reason for people to realize that the body may not respond, but also stress can produce sometimes very strange results in a man’s (or woman’s for that matter) body that can manifest a variety of problems that one might think are not connected, but yet are. Virility, libido, and potency are sometimes affected by stress as well.

To cap this, both ornithine and arginine are the two amino acids for men that can easily be supplemented for men’s health support, specifically with sexual dysfunction such as erectile capabilities. Both of these amino acids are found in meats, eggs, and fish, and in lesser amounts in dairy, nuts, wheat, rice, and soybeans.

Both arginine and ornithine can generally be purchased at any supplement section of the supermarket or natural health food store, generally as powders, tablets, and capsules. Please check with your doctor to be sure you do not have something more serious going on with your health if you are experiencing erectile dysfunction.

Reference:

http://www.aminoacid-studies.com/areas-of-use/virility-and-libido.html

Antiaging Treatments – GABA Amino Acid, Lifestyle, or Ikaria?

Antiaging treatments have included creams and lotions, or even food and potions. People and even experts say things like… drink this, eat that, live here, go there, exercise more, eat less, eat healthier, live in the Andes mountains, take this supplement (like GABA amino acid), take that supplement (like Reishi medicinal mushrooms). 

Antiaging may even include a move to Ikaria (known as Icaria, a Greek island) like Stamatis Moraitis did, according to the New York Times article entitled: The Island Where People Forget to Die, discussing how he overcame cancer merely by choosing to move back home and altering his lifestyle. Stamatis Moraitis is a centenarian, meaning he is over one hundred years old, and still alive and well, sharp as a tack, and happy and healthy.

Anti-aging techniques and treatments for some people may or may not include GABA amino acid supplements, or a lot of small changes in lifestyle (or major ones, depending), but one thing is for sure… it is not usually just one thing, but a combination of many. Longevity can include heredity/genetics as well as environmental factors.

Longevity and aging gracefully may include supplements like GABA amino acid

Aging is associated with the body’s cells breaking down over time and not functioning at the levels that they used to when people were younger. Cells die and are not regenerated the same way. To overcome physical or biological entropy it is often recommended that not just living somewhere or eating a certain way is key (although both can promote health benefits, depending on the person), but sometimes changing all the “little things” in life so that they add up to become the “big things” all by themselves.

Little things can include dietary changes, exercise regimens, breathing techniques and yoga, distressing, skipping fast food and eating fresh fruit instead, and even taking GABA amino acid supplements.

What can GABA amino acid supplements do for you?

According to a demographic study by SV Ukraintseva, KG Arbeev, et al., on antiaging treatments, many of them legally prescribed for thirty years, more or less, some of the “most common of the relevant medicines are nootropic piracetam, gamma-aminobutyric acid (GABA), selegiline, Ginkgo biloba, pentoxifylline, cerebrolysin, solcoseryl, ergoloid, vinpocetin, sertraline, and estrogens, among others.” GABA amino acid is one of these popular items used for supplementation and antiaging.

GABA amino acid can have a variety of effects on your body, mind, and health. A general overview is covered in the article What Can GABA Amino Acid Do For Me?

GABA amino acid is also used to feel better, especially when one is in pain. Kill the Pain with Amino Acid GABA – Gamma-aminobutyric acid: Nature’s Pain Killer is an article on this very topic. Isn’t part of growing old feeling good and not being subject constantly to joints and inflammation, aches, and pains?

Additionally, protecting your brain and stimulating your senses and memory are key factors. Learning a language, or even knowing what GABA amino acid supplements can do to help your brain and memory or cognition can be read about here in Amino Acid GABA Vital For Normal Brain Activity And Memory. Memory is often a problem with dementia and Alzheimer’s as one gets older.

Although GABA amino acid is not the cure-all for all ailments, it is one of the many “little things” one can do to reduce pain, combat aging and restore a sense of youthfulness, health and wellness, and memory abilities. Perhaps it could still be included in many peoples’ little box of secret weapons against aging.

Sources:

http://www.ncbi.nlm.nih.gov/pubmed/15246996

http://www.nytimes.com/2012/10/28/magazine/the-island-where-people-forget-to-die.html?smid=fb-share&_r=0

Glutamine: The Anti-Aging Amino Acid for Your Skin

Anti-aging amino acids like glutamine may help your skin appear more youthful. Aging causes our bodies’ cells to break down or regenerate as they did in our youth. Cells die but do not renew at the same rate for healing or health like when we were young. 

The triggers for aging can include DNA, but many times environment also plays a role. This environmental impact can include diet… anti-aging amino acids like glutamine can include essential and non-essential amino acids.

Essential aminos can be gotten through diet, whereas non-essential aminos are made by our bodies; but as we grow older our bodies do not always produce what we need and may require supplementation. Glutamine is a non-essential amino acid.

Anti-aging amino acids include glutamine for acid-base balancing and firming of skin

Consider glutamine (L-glutamine) for acid-base balancing and firming of the skin. Proper nutrients, such as is found in a raw food diet, while eliminating or vastly reducing disease-causing hyperacidity foods like fast foods, “white foods” (sugar, white flour, white rice and potatoes), coffee, excess meat, or nicotine, is one of the major components to healthy skin and anti-aging all the way around.

Glutamine aids the acid-base balance in the body by moving ammonia out of the kidneys. By ridding acid from the body, and the preservation of bicarbonate, the acid levels are neutralized. Glutamine is a massive supporting factor in this acid-base balance.

We are not able to support anti-aging amino acids like glutamine in the body even though it is a non-essential amino acid, because as we age our ability to produce aminos—just like the ability to regenerate cells—reduces in volume and quality, causing aging effects.

Please discuss the inclusion of the amino acid glutamine in your diet or through supplementation with your doctor or naturopathic physician. Glutamine just might be able to help your skin look younger, while also providing you with an acid-base balancing that is a necessary component of a healthy diet and lifestyle to keep you looking young!

Reference:

http://www.aminoacid-studies.com/areas-of-use/anti-aging.html

Whey Protein: The Superfood that Slows Aging – Amino Acids and Glutathione

Lots of chatter has been going on about so-called Superfoods these days, such as spinach being packed with nutrition, when vegetables like swiss chard have far more nutrients ounce-for-ounce. Similarly, there is chatter about what is or is not a Superfood, like whey protein, since it is considered a supplement rather than a whole food. However, according to Dr. Mercola—whom has written on the “Top 7 Foods That Slow Your Aging” it is whey protein that is the exception and should be added to the list. Why? Although there are a number of reasons, amino acids plus glutathione are .

Glutathione is an antioxidant produced from other amino acids. Additionally, increasing glutathione levels through food containing those amino acids brings a host of health benefits. Whey protein is one way to do this.

Anti-aging health benefits of glutathione & amino acids from whey protein

Dr. Mercola says that whey can “increase your body’s stores of the antioxidant glutathione, or GSH.” Additionally, telomeres in your DNA are in every cell in your body, and they get shorter with age; glutathione increases the integrity of telomeres since free radicals (that cause DNA mutations) tend to damage them.

Glutathione keeps us healthy. GSH levels tend to drop in people who have oxidative stress-related health issues, such as diseases like AIDS or cancer. Patients get sicker after glutathione levels drop. Eating whey can help keep your glutathione levels up.

Glutathione supplements are NOT recommended, but precursors instead

You cannot ingest glutathione directly, however, for it is actually made inside your cells from the amino acid precursors: glycine, cystine, and glutamate. So no need to take glutathione supplements… just eat foods—like whey protein—that can help your body manufacture the antioxidant glutathione you need to fight the aging process and keep your telomeres intact.

Dr. Mercola states that biologists are now saying that lengthening telomeres actually may REVERSE aging, and a flurry of excitement is spinning around this concept in medical and research circles on antiaging methods.

Mercola states that the “best way to increase and maintain your GSH (glutathione) levels is to make sure your diet includes foods (such as animal foods and eggs) rich in the sulfur amino acids your cells need to synthesize glutathione. Whey protein is the easiest and most convenient way to do this.”

Just be sure, Mercola warns, that the whey protein you consume is not just any variety, because it needs to be “high quality and very carefully processed from grass fed organic cows to preserve the fragile amino acid precursors.”

It comes down to the quality of food that we are putting into our bodies, and ensuring that we take care of ourselves daily, in order to help reverse the aging process.

Reference:

http://articles.mercola.com/sites/articles/archive/2010/02/27/top-7-foods-that-slow-your-aging.aspx

L-tyrosine And Vitamin D Links to Aging, Cognitive Decline

An animal study has led to greater understanding of the complex causes of cognitive decline in the aging brain. Cognitive decline is a factor in aging, but can this decline be prevented?  A study measured l-tyrosine nitration to investigate the role of Vitamin D in the aging brain.

The world population is aging. We can all expect to live longer, particularly if we live in developed countries. The percentage of people 80 and older is projected to increase fourfold over the next 50 years. And the proportion of people who live beyond the age of 100 is growing rapidly.

However, aging brains often suffer cognitive decline. Forgetfulness, inability to maintain focus, and a reduced capability to solve problems are common to all aging brains. Mild cognitive decline is an expected part of aging. But cognitive decline doesn’t affect all brains equally.

Cognitive decline can be caused by a variety of factors. Oxidative stress, which leads to free radicals damaging healthy cells, is one factor. Nitrosative stress is also a factor in cognitive decline. This occurs when nitrogen species act with reactive oxygen species to damage the healthy brain cells. But where does l-tyrosine fit into this picture?

A study from the Sanders Brown Center on Aging, University of Kentucky, examined the links between vitamin D deficiency and nitrosative stress. Can measuring l-tyrosine levels in the vitamin D-deficient brains help predict cognitive decline? Researchers J Keeney, S Forster, et al, developed an animal study to investigate.

Can measuring l-tyrosine combat cognitive decline?

Middle aged male rats were divided into three groups and fed either low vitamin D food, or high vitamin D food.  The diet continued for 5 months, then their brains were examined for evidence of oxidative and nitrosative stress.

One indication of nitrosative stress is the production of nitrol-tyrosine, which is caused by l-tyrosine nitration, which is a chemical process. L-tyrosine is an amino acid, produced in the body from phenylalanine. It is vital to general metabolism.

In this rat study, the low vitamin D group had much higher levels of nitrol-tyrosine. The study proved that vitamin D deficiency resulted in significant nitrosative stress in the brain, and that this nitrosative stress may cause cognitive decline.

The researchers concluded that proper nutrition, with adequate levels of vitamin D that help prevent l-tyrosine nitration, are necessary to prevent cognitive decline.

Sources:

http://www.ncbi.nlm.nih.gov/pubmed/23872023

Sulfur-Containing Amino Acids Cysteine and Methionine

The two main sulfur-containing amino acids are cysteine and methionine; however, there are other sulfur-containing amino acids as well. Both cysteine and methionine are nonpolar as well as hydrophobic, with methionine being extremely hydrophobic as far as amino acids go. Methionine is also found inside proteins, and cysteine is often found there too. There are some other fascinating things about these two (and other) sulfur-containing amino acids.

Aside from methionine and cysteine being most popularly known, other commonly known sulfur-containing amino acids include homocysteine and taurine. The last two are not incorporated into proteins, however. According to the authors at the Journal of Nutrition (JN), the “difference accounts for some of the distinctive properties of the sulfur-containing amino acids. Methionine is the initiating amino acid in the synthesis of virtually all eukaryotic proteins … [and if] exposed, are susceptible to oxidative damage. Cysteine, by virtue of its ability to form disulfide bonds, plays a crucial role in protein structure and in protein-folding pathways.”

The authors of JN discuss a number of these sulfur-containing amino acids—methionine, cysteine, taurine, homocysteine, and the lesser known S-adenosylmethionine.

Importance of sulfur-containing amino acids

Although cysteine and methionine are the primary sulfur-containing amino acids due to being two of the 22 common amino acids that are incorporated within proteins, both taurine and homocysteine are also important for physiological function. So why is sulfur in amino acids since most aminos are made of carbon, oxygen, hydrogen, and nitrogen? Because, says JN, oxygen and sulfur both belong to ‘Group 6’ of the Periodic Table of Elements, so are “capable of making similar covalent linkages” with a critical difference that sulfur has a low electronegativity (oxygen has the second lowest electronegativity). So if oxygen replaces the sulfur it would “result in a much less hydrophobic amino acid.”

Furthermore, substituting oxygen for sulfur—causing oxidation—in sulfur-containing amino acids (including in the more rare S-adenosylmethionine) can have effects in methionine residues where the surface is exposed, causing an oxidation-reduction cycle, imparing the activity of “methionine sulfoxide reductase and the subsequent accumulation of methionine sulfoxide residues [that] are associated with age-related diseases, neurodegeneration, and shorter lifespan.”

Lastly taurine, as one of the more remarkable sulfur-containing amino acids, has very high concentrations within muscle tissues and utilizes a wide variety of functions. Taurine is, says JN, the “most abundant free amino acid in animal tissues [even though it] accounts for only 3% of the free amino acid pool in plasma, it accounts for 25%, 50%, 53%, and 19%, respectively, of this pool in liver, kidney, muscle, and brain.” It is also one of the most necessary sulfur-containing amino acids for cats and results retinal degeneration in kittens if the mothers are not fed a taurine-rich diet. Taurine is also found in human mother’s milk and is added to many infant formulas because it helps with eyesight.

So all in all, sufur-containing amino acids are necessary for proper health of both animals and humans in the proper biological functioning and growth, as well being associated with some diseases and anti-aging and neurological issues.

Reference:

http://jn.nutrition.org/content/136/6/1636S.full