Amino Acids — The Good, and the Bad.
Protein, too much, too little, should I stick to whole foods, should I supplement, if I supplement, should I used protein powders, or amino acids, tablets, capsules, drinks, gels… ugg!
With so many people choosing vegetarian, vegan, and other low-protein diets — many doctors, coaches, and other health professionals recommend dietary supplementation with some form of amino acids, whether Branched Chain Amino Acids (BCAA’s) or Essential Amino Acids (EAA’s) or something in between.
BENEFITS OF SUPPLEMENTATION WITH AMINO ACIDS (BCAA’S)
Studies have suggested that supplementation with BCAAs before or during endurance exercise may improve mental and physical performance. It also may reduce protein degradation and depletion of glycogen in muscle tissue.
BCAA’s include three amino acids: leucine, isoleucine, and valine. They provide the following benefits:
- Leucine plays a crucial role in the formation of hemoglobin and muscle protein synthesis.
- Isoleucine regulates blood sugar and the conversion of carbohydrates into energy.
- Valine is believed to promote muscle growth and aid in tissue repair.
Supplementation with BCAA’s prevents the normal serum decline that typically occurs during strenuous exercise. Decreased serum due to exercise typically causes a flood of tryptophan into the brain, followed by serotonin production, which may produce dizziness, fatigue, or exhaustion. For this reason, supplementation with BCAA’s is recommended among beginning athletes to prevent fatigue.
Long-term supplementation with BCAA’s may also produce an increase in muscle growth over time.
Many natural food proteins, such as meat and eggs, contain plenty of BCAA’s to meet the human body’s daily requirements. Supplementation is usually not necessary in individuals who consume a diet sufficiently high in protein (about 0.36 grams of protein for every pound of body weight) and maintain average activity levels. The average American diet contains almost twice this amount of protein, except in cases of veganism or vegetarianism, or those who maintain a reduced-protein diet to benefit kidney health. However, there is little guarantee of a healthy ratio between all of the amino acids in a high-protein diet.
It should also be noted that the use of BCAAs has been associated with dopamine depletion in the brain, leading to negative drive and cognition impacts. A study conducted at the Department of Psychiatry Research, Zucker Hillside Hospital, NY — “In healthy subjects, intact early cortical top-down processing can be acutely dysregulated by ingestion of BCAAs.”
While BCAA supplementation may not be essential for all healthy adults, depending on your circumstance, BCAA supplementation might be recommended, especially for athletes and others who put extra strain on their bodies. We’ll discuss how to use BCAAs without depleting dopamine in a subsequent post.
AMINO ACIDS YOU DON’T NEED IN A PROTEIN SUPPLEMENT
It should be noted that not all amino acids provide the same benefits, depending on your health context and diet, some amino acids may harm or hinder your health journey. Likewise, some can be far more beneficial than others, it all depends on your circumstance. Certain “Essential” amino acids, such as cysteine, tryptophan, methionine, and histidine, are already reasonably abundant in the average diet and may hurt health and performance. In large quantities, these amino acids are precursors of conditions that produce stress, inflammation, and weakened metabolic activity.
Bear in mind also that the term “essential” is a category that is under review. Recently tryptophan has been proposed to be reclassified non-essential for protein synthesis and methionine to be labeled as essential only in doses of up to 200mg daily. Conversely, glycine, taurine, and alanine may be classified as necessary on the other hand.
Let’s take a more in-depth look at these four amino acids; cysteine, tryptophan, methionine, and histidine.
CYSTEINE
Cysteine may enter the body in two ways: through the consumption of foods that contain cysteine or through a metabolic pathway that eventually converts the amino acid methionine to cysteine.
Cysteine is believed to provide adequate protection against free radical damage, help rid the body of metal ions and harmful chemicals, and assist in treating respiratory problems (such as asthma) by reducing mucus build up in the body. It is also believed to preserve the skin’s elasticity and the lining of the stomach and digestive organs.
Nonetheless, in large quantities, cysteine may produce allergic reactions and digestive disturbances such as nausea, vomiting, and diarrhea. Since our diets already contain plenty of cysteines, it is not advisable to take this amino acid supplement.
TRYPTOPHAN
We’ve all heard of tryptophan or the substance in Thanksgiving turkey that is believed to cause drowsiness. Tryptophan is considered an “essential” amino acid because the body can’t produce it independently. It must obtain it through the consumption of certain types of foods, specifically animal and plant proteins.
Tryptophan contributes to the development and function of many organs. Through a complex metabolic process, our bodies eventually convert ingested tryptophan to serotonin, melatonin, and vitamin B6. Serotonin is a hormone that causes changes in brain chemistry and may alter an individual’s moods. Melatonin is an important hormone that contributes to restful sleep, and vitamin B6 contributes to the metabolism of energy.
While some people find tryptophan useful as a sleep aid, excess quantities of tryptophan are associated with a condition known as eosinophilia-myalgia syndrome (EMS). This short onset type of illness produces severe, disabling, neurotoxic reactions. These include chronic muscle pain, symptoms affecting the skin, and other adverse reactions.
METHIONINE
Methionine is another amino acid that is abundant in meat, fish, dairy products, and some vegetable sources. It contributes to too many cellular functions in the body.
Methionine is useful in preventing and treating liver damage in cases of acetaminophen (Tylenol) poisoning. It also increases the acidity of urine and is used to improve wound healing and treat alcoholism, allergies, asthma, copper poisoning, depression, drug withdrawal, liver disorders, Parkinson’s Disease, schizophrenia, and side effects caused by radiation treatments.
Still, methionine as a dietary supplement is risky, given that this amino acid is plentiful in our diet. Ingesting too much of it can increase homocysteine levels in the blood, increasing the risk of heart disease and conditions such as arteriosclerosis. Additionally, excessive quantities of methionine may contribute to the growth of some types of tumors, and in some cases, produce effects as severe as brain damage and death.
HISTIDINE
While histidine is an amino acid often used to treat rheumatoid arthritis, allergies, ulcers, and anemia resulting from kidney failure or dialysis, some serious risks are associated with the ingestion of excessive quantities of histidine. In people with a deficiency of folic acid, histidine may cause a harmful chemical known as formiminoglutamic acid (FIGLU) to build up in the body. With histidine being plentiful in the average Western diet, there is no need to run the supplementation risk with this amino acid.
Wrap up
Hopefully, after reading this, you will have a deeper appreciation for the importance of being selective in your choice of amino acids, whether they come from whole foods or supplements. Be cautious and choose carefully because it’s more than just money; it’s your health.
References
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