There are many amino acids in nature. About 500 are known. 20 are referred to as “standard amino acids”. Of those 20, 9 are known to be essential for humans. In this case, essential means that they must be present in the foods we eat because our bodies cannot produce them.
The ones listed below are the 5 that you can’t do without. You need to make sure that you are getting enough of them in your daily diet, either through foods or supplementation. The reasons “why” are listed in each amino acid section. In addition to the benefits of specific amino acids, all of them are building blocks used to make every cell of the body. They are obviously very important. Here are the specifics.
Tryptophan was widely recommended for depression prior to the introduction of Zoloft and other popular anti-depressants.
An isolated case of contamination caused the supplement to be banned for years but it is now readily available over the internet. 5-HTP (hydroxyl-tryptophan) is preferred by some supplement manufacturers because it can be derived from seeds and is a direct precursor in the production of serotonin, one of the brain’s feel-good chemicals.
No adverse effects have been seen from supplementation with either tryptophan or 5-HTP, even when large doses were given.
In addition to being useful in the treatment of depression, the supplements may also be beneficial for fibromyalgia, sleep disorders, anxiety, migraine headaches and tension headaches. Tryptophan was recently shown to be an immune system modulator explaining the benefits seen in autoimmune diseases and inflammatory conditions.
The benefits in immune system modulation are also relevant in cancer prevention. Inflammation plays a role in cancer. Immune system modulators help to minimize inflammation throughout the body.
Reducing tryptophan intake is sometimes recommended for people with irritable bowel syndrome. If you have IBS and supplementation seems to worsen the symptoms, you can reduce the dosage. 5-HTP supplements may also be an alternative.
Dietary sources of tryptophan include meats, fish and nuts. Turkey and egg whites are among the best sources, as the concentration of tryptophan in those foods is relatively high. Vegan sources include sesame seeds and sunflower seeds. Soybeans are the best vegan source.
The benefits of Histidine may be related to a peptide called Carnosine. Your body uses Histidine to make Carnosine, which is the only nutrient known to prevent the formation of Advanced Glycation End-products, aptly referred to as AGEs.
These protein-glucose molecules are involved in the aging process. The glucose binds with the protein making it unusable. When the molecules get inside of cells of the body, they actually kill the cell. AGEs are believed to be involved in many diseases including Alzheimer’s and type II diabetes.
Recent studies have shown that Histidine has chelating activity. Nutrients with chelating activity help to break up toxic heavy metals that get into the body from a variety of sources. After breaking up the metals, chelating agents help with their disposal.
Other benefits that have been seen in studies include the prevention of free radical damage and lipid oxidation. Lipid oxidation plays a role the plaque formation that leads to heart disease. Researchers believe that Histidine supplementation may help to prevent many age related disorders including eye disease and neurological disorders.
Most recently, Histidine supplementation was shown to improve insulin resistance and reduce inflammation in obese women with metabolic syndrome. So, the amino acid not only has preventative value but also therapeutic benefits.
Methionine is one of only two sulfur-containing amino acids. Sulfur is necessary for healthy thyroid function. The functions of the thyroid gland are numerous. Problems that accompany an unhealthy thyroid include skin disorders, hair loss, thin nails, weight gain or loss, joint pain and may others.
New studies have shown that methionine reduces bone loss in osteoporosis. Osteoporosis is a degenerative bone disease that is very common in elderly people, especially elderly women.
Methionine plays a role in the synthesis of many other amino acids; those that are not essential because your body can produce them. The very important SAM-e is derived from methionine. SAM-e is found in every cell of the body. It is involved in energy transport and energy use. Lack of SAM-e is associated with an increased risk of depression.
Age related hearing loss may also be caused by methionine deficiency. Research has shown that deficiency at any age can cause hearing loss.
Methionine supplements are available. Vegetarians are most likely to need supplementation, as there are few vegan sources of the amino acid. Brazil nuts are among the few good vegan sources.
While protein supplements are commonly recommended for body-building or fat loss, Leucine is the only one of the amino acids that has been shown to actually stimulate muscle protein synthesis within the body. It is for this reason that most modern body-building supplements are now rich in Leucine.
The amino acid has also been shown to prevent muscle atrophy. This is an important benefit for people recovering from surgery or a sports injury.
Supplementation is also associated with improve athletic performance and reduced fatigue. The fatigue reduction is believed to be due to the glycogen sparing activity of Leucine. When the muscle’s glycogen stores become depleted, you get the feeling you have “hit a wall”. Your muscles feel exhausted.
New studies have shown that Leucine protects against insulin resistance, which plays a role in type II diabetes. The supplement also decreases fat storage and is involved in regulating food intake, which means it may be beneficial for weight loss.
There is a downside. Too much of even a good thing is bad. Leucine toxicity can be life threatening. Over the short term, excessive Leucine intake causes diarrhea and dermatitis, red, dry skin.
Over the long term excessive Leucine can cause pellagra, which is usually caused by a niacin deficiency. Pellagra can lead to dementia and death. Researchers are not yet sure how excessive Leucine causes pellagra. It is assumed that the amino acid interferes with niacin absorption.
Like the other amino acids, Leucine is found in all meats and fish. Good vegan sources include pinto beans, lentils and chickpeas.
Lysine is unique because of its antimicrobial activity. It has anti-viral and anti-bacterial activity. Numerous studies have been conducted concerning the benefits for people with herpes. The benefits may include a reduced number of outbreaks.
It has proven benefits for lung function, even in the presence of lung disease. It works to thin mucus and liquefy sputum.
The amino acid is also needed for the production of collagen and elastin. Best known for their contribution to firm youthful skin, collagen and elastin also work to keep the blood vessels flexible and strong. Just as the skin cells are repaired and replaced on a regular basis, the cells of the blood vessel walls are also replaced.
Good dietary sources include egg whites, red meat, cod, sardines, catfish, soybeans, lentils, parmesan cheese and milk. Many supplements also contain lysine.
Now you know about the five amino acids that you simply cannot do without, judging from the results of recent research. Together, along with important herbal extracts, vitamins and minerals, these five may help you live a longer, stronger life.
If you're interested in a good multi-nutrient supplement, you can check out the What We Take section to learn more about how to choose a high quality product for your health.