Background

Methionine is an essential amino acid found in meat, fish, and dairy products. Amino acids are the building blocks used to make proteins.

Methionine cannot be made by the body, so it must be consumed in the diet. It plays an important role in the many functions within the body. It may also act as an antioxidant and help to protect damaged tissues.

People use methionine for preventing birth defects. It is also used for liver disorders, viral infections, breast cancer, and many other conditions, but there is no good scientific evidence to support these uses.

Safety Safety definitions

When taken by mouth: Methionine is commonly consumed in foods. It is possibly safe when used as medicine under the supervision of a healthcare provider. But methionine is possibly unsafe when used for self-medication. Too much methionine can cause brain damage and death. Methionine can increase blood levels of homocysteine, a chemical that may cause heart disease, and might also promote the growth of some tumors.

Special Precautions & Warnings:

Pregnancy and breast-feeding: Methionine is commonly consumed in foods. There isn't enough reliable information to know if methionine is safe to use in larger amounts as medicine when pregnant or breast-feeding. Stay on the safe side and stick to food amounts.

Children: Methionine is commonly consumed in foods. There isn't enough reliable information to know if methionine is safe to use in larger amounts as medicine without the care of a healthcare provider.

Acidosis: Methionine can cause changes in acidity of the blood and should not be used in people with a condition called acidosis.

"Hardening of the arteries" (atherosclerosis): People who have atherosclerosis should not take methionine. Methionine might make atherosclerosis worse.

Liver disease, including cirrhosis: People who have liver disease should not take methionine. Methionine might make liver disease worse.

Methylenetetrahydrofolate reductase (MTHFR) deficiency: People who have this disorder should not take methionine. Methionine might make this disorder worse.

Schizophrenia: Large doses of methionine might cause confusion, agitation, and other similar symptoms in people with schizophrenia.

Effectiveness

Dosing & administration

Methionine is an essential amino acid found in meat, fish, and dairy products. It's recommended that adults consume 13 mg/kg in the diet daily. Recommended amounts for children depend on age.

As medicine, there isn't enough reliable information to know what an appropriate dose of methionine might be. Speak with a healthcare provider before using.

Interactions with pharmaceuticals

It is not known if Methionine interacts with any medicines. Before taking Methionine, talk with your healthcare professional if you take any medications.

Interactions with herbs & supplements

There are no known interactions with herbs and supplements.

Interactions with foods

There are no known interactions with foods.