What Is Choline?

Choline is an essential nutrient found naturally in foods and produced in small amounts by the liver. Both plants and animals need choline to maintain cell structure. In humans, choline helps synthesize acetylcholine, one of seven major neurotransmitters responsible for many nervous system functions. Choline is also an integral part of a number of other physiological processes, including metabolism and lipid transport.

Your body does not make all of the choline that you need, so you must consume the rest from your diet. Choline can also be found sold as a nutritional supplement.

Choline and Brain Function

Neurotransmitters help neurons communicate with each other throughout the body. A portion of choline is converted to acetylcholine, a neurotransmitter that triggers muscle contraction, activates pain response, and aids memory and thought processes. The majority of choline is converted to phosphatidylcholine, a major phospholipid that helps build fat-carrying proteins.

Dietary Sources

Dietary Guidelines for Americans states that most choline should be consumed through your diet. Foods that contain choline include: 

• Animal-based foods, such as meat, eggs, dairy, and fish
• Non-animal sources including nuts, seeds, whole grains and legumes
• Apples, tangerines, kiwi, and cruciferous vegetables like broccoli and cabbage

How Much Choline Do You Need?

Choline levels are not regularly screened in healthy people. Not enough evidence is available to provide a recommended dietary allowance (RDA) for choline, but an adequate intake (AI) has been established, measured in milligrams (mg) per day. AI levels determine nutritional sufficiency: 

• Birth to 6 months: 125 mg/day
• 7-12 months: 150 mg/day
• 1-3 years: 200 mg/day
• 4-8 years: 250 mg/day
• 9-13 years: 375 mg/day
• Adolescent girls aged 14-18: 400 mg/day
• Adolescent boys aged 14-18: 550 mg/day
• Women aged 19 or older: 425 mg/day
• Men aged 19 or older: 550 mg/day
• During pregnancy: 450 mg/day
• When lactating: 500 mg/day 

People who menstruate may not need to consume the recommended AI amount because estrogen stimulates the production of choline.

Can You Take in Too Much Choline?

The tolerable upper intake levels (TUIL) for choline is 3,500 mg for adults (including during pregnancy and lactation), 3,000 mg for adolescents 14-18 years, 2,000 mg for children 9-13 years, and 1,000 for children aged 1-8 years. 

There are a few studies evaluating the impact of choline intake on health, but the data is inconclusive. One study found an association between taking high levels of choline and increased mortality.

Researchers speculate it could be because of an increased production of trimethylamine N-oxide (TMAO), a metabolite that is linked to higher risk of cardiovascular disease. 

Who Is at Risk for Choline Deficiency?

Choline deficiency is rare. Normal levels of choline vary from 7 to 20 micromoles per liter in non-pregnant adults. 

Research has shown that not consuming choline-rich foods for a week does not cause levels to decrease below 50% of what is normal. But there are some conditions that increase the risk of deficiency. These include pregnancy, genetic conditions, or being fed intravenously.  

Signs of deficiency are:

• Muscle damage
• Liver damage
• Nonalcoholic fatty liver disease (NAFLD)

A Word From Verywell

If you have concerns about your choline levels and how it may be affecting your health, talk with your healthcare provider. If you are pregnant, review your risk of deficiency with your prenatal care provider. Consult with a healthcare professional before taking any supplements.