Choline – The Lesser-Known Essential Nutrient

Have you ever heard of choline? If not, that’s understandable since this lesser-known micronutrient is not presently included in UK dietary guidelines, food composition databases, or dietary surveys¹. This isn’t the case everywhere, for example, the United States² and Norway³ have choline recommendations.

What is Choline?

Choline is an essential nutrient which is required for neurotransmitter synthesis (acetylcholine) and has physiological roles in the human body across the lifecycle⁴. Although not a true vitamin, it’s often grouped in the B-vitamin family. It can be produced in the liver, but only in very small amounts which are not high enough to fuel the bodies physiological demands and requirements can also depend on a genetic variants in genes⁵. Therefore, it is important to consume choline from the diet.

What Does Choline Do?

Choline performs a wide variety of functions in the body. Several health claims have been authorised for choline which include that choline contributes to normal lipid metabolism, normal homocysteine metabolism and the maintenance of normal liver function^6,7.

These are some of the key roles of choline:

• Normal homocysteine metabolism^6,7

• Normal lipid metabolism^6,7

• Maintenance of normal liver function^6,7

• Brain growth, development, and neurotransmitter synthesis (acetylcholine)⁸

• Methylation of genes (gene expression)⁸

• Cellular membrane structure and function (phosphatidylcholine)⁸

Pregnancy and Early Development

Choline is exceptionally important during the first 1,000 days of life (conception to 2 years) as there is growing evidence that it could help to facilitate normal brain development during this life stage when demands for choline are high⁹. For example, tissue expansion, the synthesis of new membranes, gene expression, neurotransmission and brain development are all working overtime during this life stage¹⁰!

Early work¹¹ suggested that choline can modify the foetus’ brain and spinal cord structure (through apoptosis and stem cell proliferation) influencing the risk of neural tube defects and memory function. Several decades on a gold-standard meta-analysis paper has shown that lower maternal choline intakes/blood levels were associated with a higher odds ratio (a measure of association between an exposure and outcome) for neural tube defects¹². There is also growing evidence that maternal choline supplementation could lesson cognitive and affective dysfunction when taken by mothers carrying a foetus with Down syndrome¹³.

During lactation, intake of choline and genetics influence the choline concentrations in human breast milk, which can affect the amount of choline the baby will receive¹⁴. Human neonates are also born with choline blood levels around three times higher than maternal levels, indicating high demands during this life stage.¹⁵

Liver Function

One of the key roles of choline is the maintenance of normal liver function. The recently updated 2023 Nordic Nutrition Recommendations conclude that a choline-free diet can result in liver damage (corrected by giving 500 mg choline/d)³.

How Much Choline Do We Need?

The amount of choline we need ranges from 140 – 520 mg/d depending on our life stage, and Table 1 shows the Dietary Reference Values set for choline by the European Food Safety Authority (EFSA).

Table 1: EFSA Dietary Reference Values for Choline¹⁶.

Life Stage	Amount (mg/d)
Infants (7-11 months)	160
Children (1-14 years)	140 - 340 mg
Teenagers (15-17 years)	400
Pregnant women	480
Lactating women	520
Adult males and non-pregnant females	400

The recently updated 2023 Nordic Nutrition Recommendations also include and report on choline. They specify that pregnant and lactating women and children are more likely to be vulnerable to deficiencies³. They report that there is insufficient data to derive an Upper Limit (UL)³.

Choline Intakes

Several publications have looked at choline intakes across the lifecycle. In the United States choline intakes have found to be associated with levels of egg and protein consumption (meat, seafood and poultry) with egg consumers having higher choline intakes compared with non-consumers (525 versus 294 mg/d)¹⁷. Derbyshire et al. (2021)¹⁸ reviewed evidence from 26 publications focused on the childbearing years (preconception, pregnancy, and lactation) finding that average choline intake ranged from 233 mg/day to 383 mg/day and were lower than recommended. Choline intakes are not presently collected in the UK National Diet and Nutrition Survey.

Sources of Choline

Choline can be found in a variety of foods as shown in Table 2. Although many animal sources are typically considered the highest source, Quorn’s mycoprotein provides a comparable fungi-based source of choline as shown in this infographic.

Food	Choline content (mg/100g)	Choline (per portion)
Eggs, hard-boiled	292	175.2 (60g)
Quorn Mycoprotein	180	158.4 (in 100g Quorn mince)
Oily fish (salmon)	90.5	108.5 (120g)
Lean chicken	78.8	94.6 (120g)
Tofu, fried	106	84.8 (80g)
Lean beef	84.9	76.4 (90g)
Baked beans, canned	30.8	61.6 (200g)
Quinoa, cooked	23	34.5 (150g)
Broccoli, boiled without salt	40.1	32.8 (80g)
Brussels sprouts, boiled without salt	40.6	32.5 (80g)
Cauliflower, boiled without salt	39.1	31.3 (80g)
Mushrooms, white, stir fried	21.9	17.5 (80g)
Spinach, raw	19.3	15.4 (80g)
Peanuts, raw	52.5	10.5 (20g)

_{Source: USDA FoodData Central. Available at: https://fdc.nal.usda.gov/}

Summary

Choline has been overlooked as a micronutrient but evidence in the field of choline and health is building. We have seen how choline has important roles across the life cycle, especially pregnancy when requirements increase. It can be found in many foods and Quorn^TM (mycoprotein) is one of these.