Methylmalonic Acid Unit Converter

Methylmalonic acid (MMA) is a substance produced in small amounts during protein metabolism. It is an intermediate in the breakdown of certain amino acids (isoleucine, valine, methionine, and threonine) and odd-chain fatty acids.

Vitamin B12 (cobalamin) is essential for converting MMA into succinyl-CoA, which enters the energy-producing citric acid cycle. When B12 is insufficient, this conversion slows and MMA accumulates in the blood.

MMA is considered the most specific functional marker of vitamin B12 status, often detecting deficiency before serum B12 levels drop or symptoms appear.

MMA is produced in the mitochondria of cells throughout the body during the breakdown of certain amino acids (isoleucine, valine, methionine, threonine), odd-chain fatty acids, and cholesterol. A portion also comes from gut bacteria that produce propionate, a precursor to MMA.