Choline and liver health
A decisive factor for metabolism and future treatment approaches
Liver diseases are on the rise worldwide. Around 1.5 billion people are affected and every year around 2 million people die as a result of such diseases. It is particularly alarming that obesity and type II diabetes – which affect around 54% and 7% to 8% of adults in Germany respectively – also increase the risk of liver diseases such as “fatty liver” or liver cancer.
Unfortunately, there are currently no approved drugs for the treatment of fatty liver disease. However, an exciting approach could be the effect of choline – an important nutrient that could play a major role in liver health. Even though choline supplements are not yet explicitly recommended, this important nutrient has great potential for research. As choline is primarily processed in the liver, a deficiency could put additional strain on the liver and promote damage, a decisive factor for metabolism and future treatment approaches.
What is choline?
Choline was first discovered in animal bile in 1849 and was long regarded as vitamin B4. How exactly choline works in the body and how much of it is present in the body has not yet been fully researched. It is also exciting that the personal choline requirement is still unclear, as it depends on aspects such as diet, age, gender and genetic factors.
The body can produce choline itself, but can also absorb it through food. Whether the body’s own production is always sufficient is a matter of debate among scientists.
The National Academy of Medicine in the USA recognized choline as a vital nutrient back in 1998. Since then, there have been recommendations from various professional societies on how much choline should be consumed daily. However, these are only based on scientific estimates and are summarized in the figure below.It should be noted that an excessive choline intake of 7.5 g can cause undesirable side effects such as a fishy body odor, gastrointestinal complaints and low blood pressure. According to studies, the safe upper level (UL) is 3.5 g per day.
In Germany, the German Nutrition Society (DGE) has not yet issued a recommendation.
Which foods contain choline?
Choline is found in both animal and plant foods. The illustrations below show some examples of foods that are particularly rich in choline. Lecithin, a frequently used food additive, also contains choline. However, due to the generally low quantities consumed, lecithin makes only a small contribution to the choline supply.
1.5 hard-boiled eggs (approx. 90 g)
203, 13 mg choline
1 portion of beef liver (cooked), approx. 150 g
646.5 mg choline
1.5 portions of soybeans (dried), approx. 70 g
81.2 mg choline
1 tablespoon of linseed (approx. 15 g)
81.2 mg choline
Choline: An essential building block for liver health
Choline is essential for many vital processes in the body. It supports fat metabolism and transport, promotes communication in the nervous system and makes a decisive contribution to liver health. However, choline metabolism is also dependent on other nutrients such as amino acids and vitamins, especially methionine, vitamin B12 and folic acid. A deficiency of these important nutrients can have a negative impact on the body’s own choline production.
Food supplement with choline
Dietary supplements with choline, such as α-GPC, citicoline (CDP-choline), choline bitartrate and phosphatidylcholine (as lecithin), offer another way of meeting individual requirements. Citicoline is characterized by good absorption and tolerability and has been approved in the EU since 2013 for use in foods with a maximum daily amount of 500 mg, which corresponds to about 92 mg of choline. Choline bitartrate is often used in food supplements. However, all choline compounds have a similar effect and contribute equally to increasing the choline level in the blood.
Why is choline so important?
A well-functioning choline metabolism keeps the liver healthy and can help prevent fatty deposits that can lead to a fatty liver. However, if the body does not have enough choline available – whether due to genetic factors or nutritional deficiencies – the delicate balance can be disrupted, increasing the risk of various liver diseases.
What are the typical consequences?
- Inflammation: These can trigger stress in the liver cells and impair liver function in the long term.
- Tissue damage: Excessive deposits of connective tissue can lead to liver changes (liver fibrosis) or liver destruction (liver cirrhosis).
- Fat metabolism disorders: A choline deficiency impedes the removal of fats from the liver, which increases accumulation and the risk of fatty liver.
It is assumed that the female sex hormone oestrogen increases choline production in the body. Intestinal flora also plays a role: certain intestinal bacteria can form a compound that is suspected of promoting liver damage and cardiovascular disease if choline intake is too high. A healthy gut and functioning kidneys, which excrete excess amounts of this compound, are therefore important.
Health claims for choline currently approved by the European Food Safety Authority (EFSA):
- Normal fat metabolism: Choline contributes to the support of normal fat metabolism.
- Homocysteine metabolism: Choline supports normal homocysteine metabolism.
- Liver function: Choline is important for the maintenance of normal liver function.
Note: These health claims only apply if the food contains at least 82.5 mg choline per 100 grams or milliliters.
Prospects for the future
Research shows that choline could be a promising approach to preventing and treating liver disease. While current therapies often only have a limited effect, scientists are working on finding better and more individualized solutions. The current focus is on choline metabolism. Although the results to date are still limited, choline could play a major role with new findings.
For detailed information, further content and related literature, please visit the NuT article for professionals via the following link: Choline and liver health: key role in metabolism and potential for future therapies
Acknowledgments
Many thanks to the FH Münster, especially Janina Dapprich, Prof. Dr. oec. troph. Anja Markant and Prof. Dr. rer. medic. Tobias Fischer, for writing this article as part of the “Nutrient Compass” project.
Click here for the article on the FH Münster website: Choline and liver health | FH Münster
