Choline is an essential nutrient related to the water-soluble B-complex vitamins, folate, pyridoxine, and B12, and to the essential amino acid, methionine. It is synthesized in the body as well as consumed in the diet. The largest dietary source of choline is egg yolk. Choline can also be found in high amounts in liver, peanuts, fish, milk, brewer's yeast, wheat germ, soy beans, bottle gourd fruit, fenugreek leaves, shepherd's purse herb, Brazil nuts, dandelion flowers, poppy seeds, mung beans and other beans, and a variety of meats and vegetables, including cabbage and cauliflower.

Choline is a major building block of lecithin. Choline is a precursor to acetylcholine, a chemical used to transfer nerve impulses. Therefore, choline is believed to have neurological effects.

Choline is a product of the breakdown of the muscle relaxant^{succinylcholine, which is used extensively in anesthesia. Theoretically, choline may exhibit similar muscle relaxing effects.}

Choline is a constituent of phosphatidylcholine (PC), which is a component of cell walls and membranes. It is involved in fat and cholesterol metabolism and transport. In this form, choline aids in fat metabolism and transport away from the liver.

Pure choline is rarely used because of its undesirable side effects of fishy odor. Therefore, lecithin or purified phosphatidylcholine is more commonly used.

Beta-hydroxyethyl trimethylammonium hydroxide, CDP-choline, choline bitartrate, choline chloride, choline citrate, citicoline, cytidine 5-diphosphocholine (CDP-choline), intrachol, lecithin, lipotropic factor, PhosChol®, phosphatidylcholine, TRI, tricholine citrate (TRI), trimethylethanolamine.

Note: Should not be confused with choline salicylate, choline magnesium trisalicylate, choline theophyllinate or succinylcholine.

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Asthma (Grade: B)
Choline is possibly effective when taken by mouth for asthma. Choline supplements seem to decrease the severity of symptoms, number of symptomatic days and the need to use bronchodilators in asthma patients. There is some evidence that higher daily doses might be more effective than lower daily.

Fatty liver (hepatic steatosis) (Grade: B)
Choline, when given intravenously, has orphan drug status for TPN-associated hepatic steatosis (fat deposits in the liver).

Nutritional supplement (infant formula) (Grade: B)
Choline is likely effective when used orally as a supplement in infant formulas.

Total parenteral nutrition (associated liver dysfunction) (Grade: B)
Choline is likely effective when used intravenously to treat parenteral nutrition-associated hepatic dysfunction.

Acute viral hepatitis (Grade: C)
Many studies have assessed the use of choline for hepatitis, although, there is a lack of sufficient evidence to recommend for or against the use of choline in the treatment of acute viral hepatitis.

Allergic rhinitis (Grade: C)
Oral tricholine citrate (TRI) may effectively relieve allergic rhinitis symptoms. Further research is needed before a strong recommendation can be made.

Brain injuries (craniocerebral) (Grade: C)
Early treatment with choline alphoscerate (CA), a substrate of phosphatydylocholine and a carrier of choline, was shown to be safe. When taken as part of complex pharmacotherapy, it has shown beneficial effects on CCI patients. Additional study is needed to confirm these findings.

Coma (Grade: C)
There is a lack of sufficient evidence to recommend for or against the use of choline in coma patients. Available research is limited.

Ischemic stroke (Grade: C)
Though many studies have found promising results, others have not shown statistical significance when assessing choline for the treatment of acute ischemic stroke. Due to conflicting data, choline therapy cannot be recommended.

Muscle mass / body mass (Grade: C)
There is lack of sufficient evidence for the use of choline for changing body composition, specifically, changing body fat and lean muscle.

Parkinson's disease (Grade: C)
Data regarding efficacy of choline in the treatment of Parkinson's disease is conflicting and inconclusive.

Post-surgical recovery (Grade: C)
There is a lack of sufficient evidence to recommend for or against the use of choline in patients recovering from surgery.

Alzheimer's disease/ cognitive decline (Grade: D)
Numerous studies have assessed the use of choline in cerebrovascular diseases, memory performance, dementia and Alzheimer's disease without significant benefit.

Cerebellar ataxia (Grade: D)
Choline is possibly ineffective when taken by mouth for treating cerebellar ataxia.

Improving sports performance (endurance sports) (Grade: D)
Research has shown that choline does not significantly improve performance or delay fatigue during endurance sports.

Schizophrenia (Grade: D)
Choline has been studied in schizophrenia with negative results.