314.996.5000

Health Library

Methionine

Other name(s):

a-amino-g-methylthiol-n-butyric acid

Overview

Methionine is an amino acid which is required in protein synthesis as well as synthesis of a number of additional physiologic compounds.  

Unsubstantiated claims

Please note that this section reports on claims that have NOT yet been substantiated through scientific studies.

Methionine is an antioxidant and is thought to help protect the body from damage caused by ionizing radiation, detoxify harmful substances in the body (particularly heavy metals), and inhibit fat deposition in the liver.

In addition, methionine may help alleviate fatigue and may be useful in lessening early balding and the effects of osteoporosis.

Recommended intake

Amino acids (AAs) are available as individual AAs or in proprietary AA combinations, as well as part of multi-vitamin formulas, proteins, and food supplements. The forms include tablets, fluids, and powders. However, adequate protein in the diet should provide a sufficient source of all amino acids.

There are no conditions that increase the nutritional requirements for methionine.

Side effects, toxicity, and interactions

The use of a single amino acid supplement may lead to a negative nitrogen balance, decreasing metabolic efficiency and increasing the workload in the kidneys. In children, taking single amino acid supplements may also harmfully affect growth parameters.

Always avoid taking individual amino acids in high dosage for prolonged periods.

Women who are pregnant or breastfeeding should not use methionine supplements.

Toxicity of methionine is rare (primarily observed only in excessive dosages). 

Individuals with homocystinuria type I, an inherited disease, should not use methionine supplements.

Supplementation without sufficient intake of folic acid, vitamin B6, and vitamin B12 can increase the conversion of methionine to homocysteine. This may increase risk for cardiovascular disease.  

Additional information

Click here for a list of reputable websites with general information on nutrition.

Interactive Tools

Calculators
Try out these calculators: they're fun, they're quick, and they give you important information for managing your health.

Quizzes
Informative and often surprising, these quizzes test your knowledge of today's health concerns. Find out your score and learn more about these pertinent health issues.

Risk Assessments
Get insight into your health risks by using these assessment tools. They're easy to use and give you a quick snapshot of your likelihood to develop these common conditions.

Latest Health News
Copyright © 1997-2014 BJC HealthCare. All Rights Reserved.