Archive for 'Methionine'


Posted on 11. Jan, 2011 by .


Methionine is a sulfur containing essential amino acid and was first isolated in 1922 from casein .As one of the compounds known as a lipotrophic, a fat burner or antioxidant the others in this group include choline, inositol, and betaine. It is important in the process of methylation where methyl is added to compounds as well as being a precursor to the amino acids cystine and cysteine.

Amino acids are essential to human metabolism, and to making the human body function properly for good health. The human body, minus water, is 75 percent amino acids. All of the neurotransmitters, save one, are composed of amino acids and 95 percent of hormones are amino acids.the nutrient methionine is important for many bodily functions, including immune cell production and proper nerve function

Methionine (ME (TH) + THION + INE) is an essential amino acid, defined as one that can be obtained only through food. Methionine is the body’s primary source of sulfur. The body uses sulfur to influence hair follicles and promote healthy hair, skin, and nail growth. Sulfur increases the production of lecithin in the liver, which reduces cholesterol, reduces liver fat, protects the kidneys, reduces bladder irritation by regulating the formation of ammonia in the urine, and helps the body to excrete heavy metals.

Methionine is used to treat acetaminophen poisoning to prevent liver damage. It can be given orally or intravenously. Preparations containing both methionine and acetaminophen have been formulated for use in situations where overdose could occur.

Low levels of methionine in pregnant women have shown to increase the risk of neural tube defects (NTDs) in the fetus. These defects are caused by the failure of the neural tube to close properly during the formation of the central nervous system in the developing embryo. Mothers who have an adequate intake of methionine during the period from three months prior to conception through the first trimester of pregnancy significantly lower their risk of having a baby with a neural tube defect.

Substances, such as histamine, which can cause allergic reactions and dilate blood vessels can affect the way the brain sends and receives messages. Methionine works to reduce histamine levels in the body to allow proper synaptic function. Deficiencies in methionine levels can lead to severe mental disorders such as dementia, and in supplement form it is often prescribed for the treatment of schizophrenia. It has also been shown as a promising agent to assist with memory recall and the treatment of other mental disorders such as Parkinson’s and Alzheimer’s Disease, and for patients suffering from HIV/AIDS, attention deficit hyperactivity disorder (ADHD) in adults, fibromyalgia, and stress and anxiety.

Since 2002, cancer researchers have been studying the role of methionine in a special diet for patients diagnosed with colon cancer.

Methionine is also used by the body to manufacture SAMe, also known as S-adenosyl-methionine or S-adenosyl-L-methionine. SAMe is found in every cell in the body. SAMe has been shown to be effective as a treatment for osteoarthritis and associated joint pain, stiffness, and inflammation.

SAMe has been shown to be beneficial for most types of depression. Many studies have shown SAMe to be as effective as other antidepressant drugs, working more quickly with fewer side effects. In Europe, SAMe is prescribed more often than any other type of antidepressant.

SAMe improves and normalizes liver function. In Europe, SAMe is used in the treatment of cirrhosis and liver damage caused by alcohol.

SAMe has been shown to be effective in the treatment of fibromyalgia, AIDS-related myelopathy, and attention deficit-hyperactivity disorder (ADHD) in adults.

SAMe also assists the body in producing a wide range of compounds, including neurotransmitters such as serotonin and dopamine, as well as cartilage components such as glycosaminoglycans.

SAMe is manufactured within the body and is found in almost every tissue, but it can also be made synthetically.

Methionine can be found in meat, as well as fish, eggs, and dairy products. For vegetarians, grains and soya beans are a good source, but beans belonging to the legumes are not. Natural and synthetic methionine is also available in supplements, as well as those containing SAMe, in either capsule, tablet or powder form.

Requirements of methionine vary according to a person’s body weight, but most average-size adults need approximately 800-1,000 mg per day. Children need twice that amount, and infants require five times that amount.

Methionine supplements are often recommended by alternative medical practitioners, especially for those who are not getting a proper diet, such as vegetarians who might not be getting a balance of complete protein, athletes, people under severe stress, and anyone whose alcohol intake level is moderate to high.

Women who are pregnant or breastfeeding should talk to their doctors before using any kind of supplement. Women who are healthy and eat a well-balanced diet should not require methionine supplementation during pregnancy or while breastfeeding.

There are no known drug interactions associated with methionine, and although there appears to be no toxic dosage of this amino acid, it may cause side effects such as nausea, vomiting, drowsiness, and irritability.

Some common and significant side effects of methionine deficiency include liver damage, edema, weakness, and brittle hair. Low levels can slow normal growth and development in children. Insufficient levels in pregnant women may result in neural tube defects in infants, which are brain and spinal column disorders such as hydroencephaly or spina bifida

Groups at risk of methionine deficiency

People on low protein diets – people who are not eating enough protein foods may not get enough methionine in their diet
Vegans / vegetarian – people who are on a strict vegetarian diet may suffer from a methionine deficiency if their diet is deficient in protein
People in these groups at risk of methionine deficiency should talk to a medical professional about methionine supplements BEFORE taking them

Methionine works best with

Folic Acid
Vitamin B1 (Thiamin)
Vitamin B2 (Riboflavin)
Vitamin B6 (Niacin)
Vitamin B12 (Cobalamin)

Side effects and cautions
The evidence gained from animal studies suggests that normal diets that are high in methionine content, especially when accompanied by deficiencies of the B vitamin complex, could possibly heighten the risk of atherosclerosis – which is the hardening of the arteries. This situation may come about due to an increase in the levels of cholesterol in the blood and higher levels of a compound called homocysteine in the body. Human tests conducted in the laboratory have not sufficiently tested out this hypothesis and further study is needed. The evidence however points to the fact that high methionine intake in the diet, if combined with deficiency in folic acid, vitamin B6 and vitamin B12 levels in the body, can lead to a great increase in the conversion of methionine to the compound called homocysteine. This compound is a chemical substance connected to heart disease and stroke in patients. The link between supplemental methionine and this relationship with deficiencies of the B vitamins has not been studied and whether or not this connection is a qualified hazard for humans using supplements of methionine must be established in further studies. No severe effects health wise has been registered in any patients who supplemented with up to two grams of methionine per day, even for long periods of time.

thank you and references

Continue Reading