Choline is an essential nutrient that assists with many functions in the body. One of those functions is in conversion of the amino acid homocysteine to methionine. Other functions include fetal development and brain development. Choline deficiency impacts levels of homocysteine resulting in potential negative health consequences.
Choline's Functions
Choline is synthesized in the body in small amounts and inadequate to support the body's needs for choline. Therefore, choline is an essential nutrient since the body must supply the majority of the body's needs. Functions of choline include being a key component of membrane phospholipids -- a substance similar to fats -- as well as in creating neurotransmitters like acetylcholine and preserving renal function. Choline assists with the conversion of the amino acid homocysteine to the amino acid known as methionine.
Relationship of Choline and Homocysteine
Choline and homocysteine are closely related in one very important function in the body. Choline converts homocysteine to methionine. When this conversion happens successfully, methionine metabolism happens effectively. If choline levels are low, this conversion doesn't happen, resulting in elevated levels of homocysteine. "Today's Dietitian" explains that high levels of homocysteine are inflammatory and associated with chronic diseases like heart disease, cancer and declines in cognition. A 1998 study in the "Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline" by the Institute of Medicine discusses a relationship between choline and homocysteine in men and women fed intravenously with solutions that contained adequate methionine and folate but lacked choline. The men and women developed a condition called "fatty liver" with signs of liver damage that resolved after choline was given.
Research on Homocysteine and Choline Deficiency
A choline deficiency can have serious consequences. In a November 2009 study in "Nutrition Reviews," men ages 50 to 71 took a daily dose of choline at 2.6 g in the form of phosphatidylcholine. The supplement lowered homocysteine levels significantly and were as effective as folic acid in lowering homocysteine, explains the researchers. It is important to keep homocysteine levels at normal levels since high levels are associated with heart disease and other chronic diseases.
Guidelines to Prevent Choline Deficiency
Obtaining adequate intake of choline in the diet is essential to preventing a deficiency. Sources include milk, chicken, wheat germ, beef, pork and eggs. The body absorbs choline from eggs the best and one egg per day is adequate to meet choline needs. Choline is also available in supplemental form. The Institute of Medicine recommends 550 mg for men each day and 425 mg for women.
References
- "Today's Dietitian"; Choline --- Rethinking the Dietary Requirement; Densie Webb, PhD, RD
- "Dietary Reference Intakes: Thiamin, Riboflavin, Niacin, Vitamin B6, Folate, Vitamin B12, Pantothenic Acid, Biotin, and Choline"; Food and Nutrition Board, Institute of Medicine; 1998
- "Nutrition Reviews" Choline: An Essential Nutrient for Public Health. Ziesel, et al.; 2009
Member Comments