Choline: Benefits, Dosage, and Safety

What choline is

Choline is an essential nutrient naturally present in some foods and available as a dietary supplement. It is a source of methyl groups needed for many steps in metabolism. The body needs choline to synthesize phosphatidylcholine and sphingomyelin, two major phospholipids vital for cell membranes, so all plant and animal cells need choline to preserve their structural integrity. The liver can produce some choline endogenously (mostly as phosphatidylcholine), but not enough to meet human needs, so some choline must come from the diet. It is often grouped with the B-complex vitamins. The DRI Food and Nutrition Board classifies it among the same report as the B vitamins, though it is not formally a vitamin in the strict sense.

What it does

• Serves as a source of methyl groups needed for many steps in metabolism
• Is needed to synthesize phosphatidylcholine and sphingomyelin, phospholipids vital for cell membrane structure
• Is needed to produce acetylcholine, a neurotransmitter involved in memory, mood, and muscle control
• Plays roles in modulating gene expression and cell membrane signaling
• Supports lipid transport and metabolism, including transport of lipids out of the liver
• Contributes to early brain development

How much choline per day

These are population reference values from the NIH and the Dietary Reference Intakes. They are targets for healthy people, not personal prescriptions. The last column is the Tolerable Upper Intake Level, the most you should get from all sources combined.

Deficiency and who is at risk

Choline deficiency can cause muscle damage, liver damage, and nonalcoholic fatty liver disease (fat accumulation in the liver). The Adequate Intake is based on prevention of liver damage as measured by serum alanine aminotransferase levels. Frank choline deficiency in healthy men and nonpregnant women is very rare, possibly because of endogenous synthesis, even though most people in the United States consume less than the AI.

Who may need more

• Pregnant and lactating women, whose needs are higher and who commonly fall below the AI
• People with genetic variants (such as in the PEMT gene) that reduce endogenous choline synthesis
• People on long-term total parenteral nutrition
• People with low folate or vitamin B12 status
• Postmenopausal women, who lose the estrogen-driven boost to endogenous choline synthesis

Food sources

Richest sources are animal-based: beef liver (356 mg per 3 oz), eggs (147 mg per large egg), beef top round (117 mg per 3 oz), chicken breast and lean ground beef (72 mg per 3 oz), and cod (71 mg per 3 oz). Plant sources include roasted soybeans (107 mg per half cup), red potatoes (57 mg), wheat germ (51 mg per oz), kidney beans (45 mg per half cup), quinoa (43 mg per cup), and cruciferous vegetables such as Brussels sprouts and broccoli. About half of dietary choline in the US is consumed as phosphatidylcholine. Lecithin is a common food additive.

Forms and absorption

Supplemental forms include choline bitartrate, phosphatidylcholine, and lecithin (a substance rich in phosphatidylcholine). Choline is sold as choline-only supplements, in B-complex products, and in some multivitamin/mineral products. Typical amounts in supplements range from 10 mg to 250 mg. No studies have compared the relative bioavailability of choline from these different forms.

Safety, excess and interactions

Too much

High intakes of choline are associated with a fishy body odor, vomiting, excessive sweating and salivation, hypotension (low blood pressure), and liver toxicity. Choline consumption has been shown to increase production of trimethylamine-N-oxide (TMAO) in a dose-dependent manner. The Tolerable Upper Intake Levels were set based on the amounts of choline associated with hypotension and fishy body odor. ULs apply to healthy people, not to those taking high doses under medical supervision.

Interactions to know

• Per the NIH Office of Dietary Supplements, choline is not known to have any clinically relevant interactions with medications.

How status is measured

Choline status is not routinely measured in healthy people. When assessed, plasma choline is used; healthy adults range from 7 to 20 micromol/L (about 7 to 9.3 micromol/L when fasting). Plasma choline does not fall below about 50 percent of normal even after prolonged fasting. The AI was based on serum alanine aminotransferase (a marker of liver damage) rather than a direct choline biomarker.

Regulated as a dietary supplement ingredient under DSHEA, not as a drug; supplements are not FDA-approved to diagnose, treat, cure, or prevent disease. The FDA Daily Value (DV) for choline is 550 mg for adults and children age 4 and older. FDA does not require food labels to list choline unless it has been added to the food.

What the evidence supports

We grade the strength of evidence behind each common reason people take choline, mirroring how the NIH describes it.