ABSTRACT
Choline, an essential nutrient for humans, is consumed in many foods. It is a constituent of all cell membranes and is necessary for growth and development. Also, as the major precursor of betaine, it is used by the kidney to maintain water balance and by the liver as a source of methyl groups for the removal of homocysteine in methionine formation. Moreover, choline is used to produce the important neurotransmitter (nerve messenger chemical) acetylcholine, which is involved in memory and other nervous system functions. Maternal diets deficient in choline during the second half of pregnancy in rodents caused decreased neuronal cell growth and increased cell death in the memory center of fetal brains. This resulted in lifelong biochemical, structural, and electrophysiological changes in brains, and permanent behavioral (memory) modifications in the offspring. Dietary deficiency of choline in rodents causes development of liver cancer in the absence of any known carcinogen. In humans, dietary deficiency of choline is associated with fatty liver and liver damage. With the recent availability of a food choline content database, and with new recommended adequate intakes of choline in the human diet, further epidemiological and clinical studies on this nutrient can be expected.
