Choline is an essential nutrient but not, strictly speaking, a vitamin although it is often mistakenly thought of as a member of the B complex, with which it has numerous functions in common. Choline should be found in abundance in a normally healthy diet, but deficiencies have been linked with cardiovascular and liver disease, as well as impaired cognitive function.



Until as recently as 1998 it was believed that the body could manufacture an adequate supply of choline from the closely associated nutrients, vitamin B12 and folic acid. It is now accepted, however, that although the body can indeed synthesise choline in limited quantities, an adequate supply from the daily diet is also required for the avoidance of a number of potentially serious deficiency conditions and diseases.

Most choline in the body is contained in the phospholipids, a particular type of fat molecule of which the most common, phosphatidylcholine, more commonly known as lecithin, is also an important dietary source of choline. Choline is known to be crucial for the proper functioning of the brain's neurotransmitters, and in the form of lecithin is an important element in the composition of cell membranes and effective biochemical communication between cells.

Lecithin, moreover, is vital for the liver's ability to break down fat and cholesterol into the "Very Low Density Lipoproteins" (VLDLs) which are carried around the body in the bloodstream. Any deficiency of choline or lecithin may therefore result in the liver becoming unable to metabolise dietary fat and cholesterol in this way, and the resulting accumulation may lead to the condition known as "fatty liver" and ultimately perhaps to serious liver disease. Some research even suggests that the changes in the liver brought about by choline deficiency may lead to an increased risk of liver cancer, although not all authorities regard this research as conclusive.

VLDLs are also necessary for the production of the High Density Lipoproteins (HDLs), the so-called "good cholesterol", which is generally recognised as a significant protector against cardiovascular disease. There is also some evidence, although the research is not yet universally accepted, that choline may assist in the breaking down of homocysteine, a naturally occurring protein within the body, which is strongly associated with an increased risk of cardiovascular disease.

These protective effects may appear somewhat paradoxical, because the milk, eggs and liver which are the richest food sources of choline have been condemned in the past for the amounts of supposedly dangerous cholesterol they introduce to the body. A small (3oz) serving of beef liver, for example, will provide more than 350 mg of choline, and a single large egg perhaps 125 mg or more. So strict vegetarians who adopt a low fat, and supposedly low cholesterol diet which excludes these choline rich foods, may paradoxically be placing their cardiovascular health at risk.

Fortunately, however, this is a relatively simple problem to resolve, as supplies of lecithin manufactured from soy beans are readily available from health food stores. A single teaspoon (3.5g) of the granular supplement may provide around 130 mg of choline and is reasonably palatable when sprinkled in suitable drinks or on cereals. Peanuts and wheatgerm are also useful vegetarian sources.

To put the quantities mentioned above in some kind of context: the US Food and Nutrition Board (FNB) has recommended an "Adequate Intake" amount for choline of 550 mg a day, or a mere 4-5 teaspoons of granular lecithin and it has been estimated that most adults are able to obtain between 700 and 1,000 mg a day from a normally healthy diet. Caution should be exercised, however, in the treatment of the FNB recommendation which appears to have been set at the lowest level necessary to avoid liver damage. And it may be noted also that the 700 mg figure for the lower end of the range of normal intake seems perilously close to the 550 mg a day regarded as adequate by the FNB.

But the avoidance of serious damage to a vital organ is, to put it mildly, the very minimum one would reasonably expect of a "healthy" diet, and a very long way indeed from the optimum health which nutritional practitioners insist should be the aim.

For example, although conventional medicine remains reluctant to accept the link as proven, there is some evidence that choline in amounts of up to 1g can improve cognitive function and particularly memory. Choline is known to act as a stimulant to the production of essential neurotransmitting chemicals, and there is also some evidence that high intakes during pregnancy may encourage optimal development of the foetal brain and nervous system.

Although the possible reasons are not fully understood, there is also good evidence that high doses of choline may significantly improve athletic performance in long distance endurance events such as marathon or triathlon.

So given that the FNB has established 3.5 grams (ie 3,500 mg) a day as the upper safe limit for choline intake before any potential (and minor) side-effects might be encountered, and that choline cannot be stored in the body, there seems no reason not to aim for an intake well in excess of the recommended minimum or "adequate" amount.

Granular soy lecithin can provide a simple and convenient means of supplementation with such doses.