Isoleucine

Other Name(s):

a-amino-b-methyl-n-valeric acid

Unsubstantiated Claims:

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

Isoleucine may play a critical role in hemoglobin (the oxygen-carrying pigment inside red blood cells) production. It may regulate blood sugar level, increase energy and endurance and help speed healing of injured muscle tissue.

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 requirements for isoleucine.

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 of the kidneys. In children, taking single amino acid supplements may also harmfully affect growth parameters.

Isoleucine supplements should be taken together with leucine and valine.

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

Women who are pregnant or breast-feeding should not use isoleucine supplements.

Individuals with maple syrup urine disease (MSUD), a rare inherited disorder, should not use isoleucine or the other branched-chain amino acids (leucine or valine).

Additional Information:

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

References:

1. Weast RC, Astle MJ, Beyer WH, eds. Handbook of Chemistry and Physics. 65th ed. Boca Raton, FL: CRC Press, Inc.; 1984.

2. Lide DR, Frederikse HPR, eds. Handbook of Chemistry and Physics. 75th ed. Boca Raton, FL: CRC Press, Inc.; 1994.

3. Murray RK, Granner DK, Mayes PA, Rodwell VW. Harper's Biochemistry. 25th ed. Stamford, CT: Appleton & Lange; 2000.

4. Meisenberg G, Simmons WH. Principles of Medical Biochemistry. Mosby Pub. Co.; 1998.

5. Styer L. Biochemistry. 4th ed. W.H. Freeman & Co.; 1995.

6. Montgomery R, Conway TW, Spector AA, Chappell D. Biochemistry: A Case-Oriented Approach. 6th ed. Mosby Pub. Co.; 1996.

7. Behrman RE, Kliegman RM, Nelson EE, Vaughan VC, eds. Nelson Textbook of Pediatrics. 14th ed. Philadelphia, PA: W.B. Saunders Co.; 1992.