Studies conducted by Alan L. Buchman, M.D., associate professor of medicine at The Feinberg School of Medicine at Northwestern University, have shown that fatty liver can be prevented with the addition of the nutrient choline, a component of lecithin.
The connection between liver abnormalities and choline deficiency in humans was first demonstrated in 1993, when Buchman and co-researchers conducted a small study to establish whether choline supplementation could reverse hepatic steatosis (fatty liver) in patients who were receiving long-term total parenteral nutrition (TPN) and who had low choline levels in their blood.
Based on the results of the study, Buchman and his co-researchers concluded that fatty liver could be eliminated, if not prevented, with the addition of choline to TPN solutions.
Choline had not been put in IV nutrition solutions because it had been thought that, unlike some animal species, humans could synthesize choline on their own. It was also thought that humans metabolized choline very slowly.
"They do metabolize it very slowly, but it doesn't mean they don't metabolize it. Without a source, regardless of how slowly choline is metabolized, eventually the body's supply will be depleted," Buchman said.
Lecithin, which contains 13 percent choline, was originally given to patients receiving TPN because there was no commercially manufactured form of choline.
Also, patients who had taken pure choline orally developed body odors that smelled like dead fish. This prompted Buchman and his colleagues to develop an IV formulation of the nutrient that was stable and could be administered through TPN solutions.
"When we gave choline intravenously, we were able to get the blood levels of choline to normal and all the fat in the liver went away," said Buchman.
Buchman is currently the principal investigator of a study, funded by the Food and Drug Administration (FDA), of patients who have had their intestine surgically removed and are receiving IV nutrition or TPN. Participants in the study, which is being conducted in hospitals across the country and in England, will be given either choline or placebo in their IV solutions and monitored to see if liver damage can be prevented.
According to Buchman, there may be other implications for the use of choline beyond patients who are missing their intestines or have intestines that don't function properly.
"Although we've known about choline for a while, we're just now discovering its importance to verbal and visual memory, nerve conduction, and communication between the cells of the body," says Buchman.
Based on Buchman's research, in 2001 the FDA gave its approval for manufacturers to make nutritional content claims for foods and dietary supplements fortified with choline.
It should be noted that since choline is in virtually all foods, it is difficult for the average person to become deficient in choline. However, in a society where many people are avoiding significant sources of choline, such as organ meats and fatty foods, the dietary intake of the nutrient may be decreasing.
For alcoholics, those suffering from malnutrition and those on certain fad diets, choline deficiency is a definite possibility. Drinking alcohol significantly increases choline metabolism; therefore, alcoholics have a much greater choline requirement and are more likely to be choline deficient. Research studies elsewhere are investigating the use of choline in alcoholics to assess whether choline supplementation may prevent cirrhosis.
KEYWORDS: choline, fatty liver, liver failure, total parenteral nutrition