Choline: Foods and properties

Choline and its metabolites serve vital biological functions. They affect liver function, brain function, muscle movement, nervous system and metabolism.

In 1998, the Institute of Medicine in the United States recognized choline as an essential nutrient. However, it is not considered a vitamin because the body makes some amount in the liver in the form of phosphatidylcholine (lecithin), a phospholipid that contains choline and is deposited in cell membranes. But sometimes choline is grouped in the B vitamin complex because of its resemblance to these vitamins.

Note that while the term phosphatidylcholine is used chemically as an alternative to lecithin, they have different commercial meanings. Commercial lecithin is a lipid mixture that may contain from 10% to 90% phosphatidylcholine. Choline makes up about 15% of the weight of phosphatidylcholine. [1]

Recommended intake and basic properties

In 2016, the US Food and Drug Administration (FDA) set a Recommended Daily Intake of 550 mg per day for men and 425 mg for women (450 mg for pregnant women and 550 mg for breastfeeding women). The maximum daily safe limit for adults is 3,500 mg.

The basic properties of choline are:

• It is present in many phospholipids which make up the membranes (cellular, mitochondrial, etc.). The main purpose of choline is to be part of phosphatidylcholine which is the dominant phospholipid of cell and mitochondrial membranes. It is also present in sphingomyelin which makes up 10% of the phospholipids in the brain.
• It is required for the production of acetylcholine, a neurotransmitter involved in memory, muscle movement and heart rate regulation.
• It helps (along with vitamin B12 and folic acid) in a process that is important for DNA synthesis.

What foods is it found in?

The dietary patterns of choline in infancy differ from those in adulthood. Choline is a water-soluble molecule but lecithin (found in eggs, soy and other foods) is fat-soluble. The main source of choline in babies is water-soluble form, through human milk. Later, uptake comes mainly through fat-soluble molecules.

There are a variety of foods that contain choline. Foods of animal origin are significantly more abundant. The content, per 100 grams, of some foods rich in choline is [2]:

• Beef liver: 430 mg.
• Chicken liver: 300 mg.
• Boiled egg (yolk): 225 mg.
• Beef steak: 104 mg.
• Cooked salmon: 90 mg.
• Chicken breast: 60 mg.
• Cauliflower: Half a cup (118 ml) 24.2 mg.
• Almonds: 52 mg.
• Cooked broccoli: 40 mg.
• Milk 2% fat: 16 mg.
• Soybean oil: 1 tablespoon (15 ml) 47.3 mg.

As a dietary supplement, choline is available in tablets and capsules, often as choline chloride but also as part of lecithin.

Choline and properties for the body

Necessary for the fetus

Fetal and perinatal nutrition affect organ function in adulthood (eg blood pressure, heart disease, diabetes). Intake of choline (also iron, zinc, and folic acid) affects fetal brain development. In rodents, reduced intake leads to decreased neurogenesis in the cerebral cortex and hippocampus. Maternal malnutrition can increase the risk of neural tube defects in the fetus. It can also increase the risk of other complications during pregnancy such as preeclampsia, premature birth and low birth weight. It is no coincidence that the placenta provides large amounts of choline to the fetus. Breast milk is also rich in choline. at a concentration of 125 mg / l. up to 166 mg / l. As a result, choline levels in the blood and tissues are much higher in infants than in adults.

Contributes to homocysteine ​​metabolism

Choline (along with folic acid) helps convert homocysteine ​​to methionine. It regulates homocysteine ​​through its metabolite betaine. Homocysteine ​​damages blood vessels when it is high in the blood. Theoretically, therefore, higher choline intake may be associated with a reduced risk of heart disease. However, at present, there are no studies showing that a high choline intake benefits cardiovascular health by reducing homocysteine ​​[3].

Improves cognitive function

Choline, in addition to being essential for optimal brain development, appears to affect cognitive function in later life [4]. In an observational study involving 2,195 people aged 70-74, those with the highest choline levels also had better cognitive function. Another observational study found that insufficient levels of choline, vitamin C and zinc were associated with poor working memory in older men. In a six-month study, lecithin in people with early-onset Alzheimer’s disease moderately improved memory in one subgroup [5].

Protects the liver

Choline deficiency causes muscle damage and fat deposition in the liver. One study found that women with normal weight who had the highest choline intake had a 28% lower risk of liver disease [6]. Another study found that when postmenopausal women ate a choline-deficient diet, 73% had liver or muscle damage. These symptoms disappeared as soon as they started taking enough choline.

It can help with weight loss

It has been claimed that choline aids in weight loss. The reason for this is that it makes fat burning more efficient. Thus, some athletes use choline supplements to lose weight quickly. One study found that choline supplements in taekwondo and judo athletes improved lipid metabolism and rapidly reduced their weight [7].

Improves mental health

Choline is considered essential for the production of acetylcholine, a neurotransmitter that plays an important role in the regulation of memory, mood and intelligence. One study linked lower levels of choline in the blood to a higher risk of anxiety. Another study found that choline treatment improved the symptoms of mania in people diagnosed with bipolar disorder [8]. However, there are not many studies on mental health issues.

Groups with possible deficiency

Although choline deficiency is uncommon, not all people get enough choline. It seems that there is a significant variation in nutritional requirements from person to person, due to genetic differences. The following groups of people may be at increased risk of failure:

• Vegan: Strict vegetarians who do not eat meat, eggs and milk may have choline deficiency.
• Endurance Athletes: Levels fall during endurance sports, such as marathons.
• High alcohol intake: Alcohol may increase the need for choline.
• Postmenopausal women: Estrogen helps in the production of choline but is significantly reduced in postmenopausal women.
• Pregnant women: Choline needs increase during pregnancy because the fetus needs this nutrient to grow.

Possible side effects

Although choline deficiency can lead to adverse health effects, excessive intake can also cause problems such as hypotension, sweating, vomiting, excessive salivation, liver toxicity and fish odor.

Some of the choline we consume is absorbed while the rest is metabolized by intestinal bacteria to triethylacin (TMA), a fish-smelling substance. If choline consumption is excessive, the body may emit a fishy odor.

Triethylaine is then metabolized in the liver to trimethylamine N-oxide (TMAO), which has the effect of increasing platelet adhesion. In recent studies, high levels of TMAO in the blood have been linked to an increased risk of thrombosis, heart attack and ischemic stroke.

TMAO is thought to cause aging in blood vessels, however levels in the human body depend not only on choline consumption but also on the intestinal microbiome. People on a plant-based diet have different intestinal microbiome and produce less TMAO for the same choline intake than people who consume mostly animal products [10].

At Vita4you.gr you will find a variety of choline supplements!

References

1. Phosphatidylcholine.
2. Dietary Choline Intake: Current State of Knowledge Across the Life Cycle.
3. Usual choline and betaine dietary intake and incident coronary heart disease: the Atherosclerosis Risk in Communities (ARIC) study.
4. Choline: critical role during fetal development and dietary requirements in adults.
5. A double-blind, placebo controlled trial of high-dose lecithin in Alzheimer’s disease.
6. Higher dietary choline intake is associated with lower risk of nonalcoholic fatty liver in normal-weight Chinese women.
7.  Effect of Choline Supplementation on Rapid Weight Loss and Biochemical Variables Among Female Taekwondo and Judo Athletes.
8. Choline in the treatment of rapid-cycling bipolar disorder: clinical and neurochemical findings in lithium-treated patients.
9. The effect of lecithin supplementation on plasma choline concentrations during a marathon.
10. 10 Plant-based meat lowers some cardiovascular risk factors compared with red meat, study finds.