Methionine is an essential amino acid that is not manufactured by your body. Is a principle supplier of sulfur which improves the tone of your skin, promotes growth and conditions your hair as well as strengthen your nails. The sulphur also protects the cells from airborne pollutants, such as smog, slows down the aging process in the cells, and is involved with the production of protein. Methionine is an excellent chelator of heavy metals,such as lead, cadmium and mercury, binding them and aiding in their excretion from the body. It can help aid in some cases of allergy because it reduces histamine release.

Methionine is a nutritionally essential amino acid. It may be substituted with its corresponding keto acids, which on amination gives rise to methionine. The body cannot synthesize the corresponding keto acids. In microorganisms the methionine can be synthesized by methylating the homocystenine.

Weissbach and his associates have shown that for the methylation process, though active methionine is required yet methyl-B12 coenzyme acts as a methyl donor in transformation of homocysteine to methionine.

Methionine is sulphur containing essential amino acid and was first isolated in 1922 from casein and belongs to a group of compounds called lipotropics - the others in this group include choline, inositol and betaine. All these are glycogenic.

Sources of methionine

Methionine is found in good quantities in meat, fish, beans, eggs, garlic, lentils, onions, yogurt and seeds.

Other sources of methionine are cheese, eggs, chicken, and beef.
Benefits of methionine
It is used for treating endometriosis, a condition in which patches of endometrial tissue from the uterine lining grow outside the uterus.
It also helps in the breakdown of fats and thereby prevents the build-up of fat in the arteries, as well as assisting with the digestive system and removing heavy metals from the body since it can be converted to cysteine, which is a precursor to gluthione, which is of prime importance in detoxifying the liver.

The amino acid methionine is also a great antioxidant as the sulfur it supplies inactivates free radicals.
It may also be used to treat depression, arthritis pain as well as chronic liver disease - although these claims are still under investigation. Some studies have also indicated that methionine might improve memory recall.

It is also one of the three amino acids needed by the body to manufacture creatine monohydrate, a compound essential for energy production and muscle building.
It also helps to maintain healthy skin tone, well-conditioned hair, and strong nails.
It also helps to increase the flow of bile and cell-damaging toxins away from the liver.
It helps to relieve the bleeding, cramps, pain, and other complications of endometriosis.
Deficiency symptoms of methionine
Severe deficiency may result in dementia, while lesser deficiencies may be known by symptoms like fatty liver, slow growth, weakness, edema and skin lesions.

Symptoms of high intake

It has been suggested that a high intake of methionine, in the presence of B vitamin deficiencies, may increase the risk for arteriosclerosis (hardening of the arteries) by increasing blood levels of cholesterol and a compound called homocysteine

Excessive methionine intake, with an inadequate intake of folic acid, vitamin B6 and vitamin B12, may increase the rate of conversion of methionine to homocysteine - both these theories have not been proven in humans.
When more is needed

People with liver problems, pancreatitis, HIV/AIDS as well as Parkinson's disease may require high amounts of methionine in their diet but they should consult their physician before taking higher doses.

Older people may also benefit from a slightly higher intake of this nutrient.

Women on birth control pills could also benefit from this nutrient, since it promotes the excretion of estrogen.

People suffering from schizophrenia could require extra methionine since it reduces the level of histidine in the body, a level normally higher in people suffering from schizophrenia.

Daily requirement

The daily dosage of methionine is about 12 mg per kilogram of body weight per day - which would translate to about 840 mg for a 70 kg male.

Other points

It is used with choline and inositol.

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.

There are no known drug or nutrient interactions associated with methionine.

If you have any serious illness or are pregnant, only take an amino acid such as methionine after consulting your physician.

To be safe, never take methionine--or any single amino acid for that matter--for longer than three months unless you are under the direction of a doctor familiar with its use.