For the first time, the essential nutrient choline has been included in the Nordic nutrition recommendations. Choline has many important functions in the body and many people do not get enough of this nutrient from the diet.
The Nordic nutrition recommendations are the scientific basis for the national dietary guidelines issued by the authorities in Scandinavia and the Baltic countries.
Many would say that it is an important time to put choline on the agenda in the north as most Norwegians and Europeans do not get enough choline. Choline was first characterized as an essential nutrient and included in the recommendations in the US in 1998. In 2016, the European Food Safety Authority, EFSA, also stepped in and included choline in their Dietary Reference Values.
As an essential nutrient, meaning that the body cannot produce enough on its own, choline intake is important. Studies show that choline is especially important for pregnant women and the elderly.
What is choline and why is it so important?
Choline is a vital nutrient needed in the phospholipids that build the membranes around all the body's cells. It also plays a key role in one of the brain's most important neurotransmitters, acetylcholine. This means that our brain and nervous system need choline, among other things, to store memories and control muscles. Choline is also a building block in several metabolic processes, i.e., processes that convert air (oxygen) and food into substances that the body needs to function. Furthermore, choline deficiency is linked to fatty liver disease, and possibly also heart disease and neurological disorders such as Alzheimer's and dementia. A study on mice, recently published in Aging Cell, showed that a diet low in choline led to both organ damage and Alzheimer's-like disease. To that end, choline is very important for a variety of the body's functions.
The main sources of choline found in the Nordic countries include eggs, meat, dairy, and grain. Another efficient way to raise choline levels is to supplement with krill oil, which contains phospholipid-bound omega-3 fatty acids and choline.
Natural source of choline
The main dietary sources of choline in the Nordic countries are eggs, meat, dairy products, and grains. Since many people do not achieve the recommended amount from the diet, one could also consider taking choline supplements. Krill oil is a good alternative, because it naturally contains choline in phospholipid form, in combination with omega-3 fatty acids and antioxidants. This unique combination has made krill oil a popular dietary supplement in many parts of the world.
Important during pregnancy and breastfeeding
When the brain is developing, choline is particularly important. At birth, the baby's brain is about ¼ the size of the average adult brain, but it grows at a particularly rapid pace in the first few years, and by the age of 3, it will reach 80 percent of its full size. The brain consists of around 100 billion neurons, and these work by receiving and sending nerve impulses, i.e., electrical signals. Several studies, conducted on both animals and humans, confirm that during fetal development, choline plays an important role in the developing brain.
Since choline is a part of the phospholipids in all cell membranes, it is necessary to support rapid growth and myelination (insulation) of the neurons that form in the fetus. Neurons send electrical signals to each other, and these signals consist of a chemical neurotransmitter, called acetylcholine. As the name suggests, acetylcholine contains the nutrient choline. Acetylcholine affects many processes in the developing brain. For example, neurogenesis, cell survival, and the plasticity (moldability) of synapses (the contact points between brain cells). It also supports normal development of the hippocampus, a region of the brain with roles in learning, memory, and attention.
Animal studies have shown that choline insufficiency during pregnancy can have negative effects on the child's brain development and function, including problems with the eyes and vision. Two randomized controlled trials which investigated choline supplementation to pregnant women showed positive effects on infants' cognitive functions, and the effects even persisted up to the age of seven.
May reduce the risk of developing dementia
Choline is not only important for the developing brain, it may also protect against age-related cognitive decline. Animal and epidemiological studies have reported associations between choline intakes and cognitive functions in healthy adults and the risk of developing dementia and Alzheimer's disease among elderly.
In Alzheimer's disease, characteristic changes occur in the brain. Plaques are formed in the brain and this plaque is a form of waste product, which comes from "mis produced" proteins that deposit themselves, destroying neurons and reducing the blood flow in the brain.
A recent study showed that choline intake n prevented cognitive decline and the formation of plaques in the brains of aging mice. The mice that received choline also had lower levels of the amino acid homocysteine in the brain. Increased brain levels of homocysteine have been proposed as one of the causes of plaque accumulation. Choline, along with B-vitamins, contributes to maintaining normal homocysteine levels in the blood.
In the Framingham Heart Study (FHS), a successful, multigenerational study from the US researchers followed a sample of over a thousand people to study the connection between diet and later occurring disease. They found that those with higher choline intakes got better scores in a memory test and had a healthier brain structure as shown with brain MRI imaging. Another, recent study that also studied a sample from the FHS, found that those who reported the lowest choline intakes where at higher risk of having developed dementia or Alzheimer's when they were followed up 10 years later.
Should you take supplements?
Available data suggests that the majority of populations worldwide do not get enough choline from their diets. Certain groups in the population who are in life phases where choline is particularly important, or where the average intakes has been seen to be too low, may benefit from supplements. This applies especially to pregnant- and breastfeeding women, elderly, and vegetarians or vegans. When selecting a dietary supplement, one could look closely at the various options since choline occurs in both water-soluble and fat-soluble forms. Supplementation with the water-soluble forms (e.g. choline salt or choline bitartrate) have been associated with increased production of a molecule in the body, called TMAO, which is suggested to potentially increase the risk of cardiovascular disease. Supplementation with choline in its fat-soluble form, so-called phospholipid form, does not show an increase in TMAO. Supplements that contain choline in phospholipid form can, for example, be soy lecithin or krill oil. Krill oil is similar to fish oil in the way that it contains the omega-3 fatty acids EPA and DHA, but in addition it contains choline in phospholipid form. Therefore, it is an ideal way to obtain "two nutrients in one", while lecithin contains other fatty acids than omega-3's.