There is strong evidence that adequate choline supports normal liver functions and helps to prevent nonalcoholic fatty liver disease (NAFLD) and fatty liver, either as a result of choline deficiency or alcohol consumption.
Choline functions in liver health through a variety of mechanisms. These include abnormal phospholipid synthesis, defects in lipoprotein secretion, oxidative damage caused by mitochondrial dysfunction, and endoplasmic reticulum stress (Corbin and Zeisel, 2012).
Choline's role as part of the phospholipid phosphatidylcholine is critical in healthy liver function. It is a primary structural component of the phospholipid membrane of all cells. This phospholipid is also needed in the construction of very low density lipoproteins (VLDL), which function in fat transport.
Rodents fed choline–methionine-deficient diets develop fatty liver. They also progress to develop liver fibrosis and hepatocarcinoma (Corbin and Zeisel, 2012). Dietary intake of methyl donors, including choline, influences the methylation of DNA and histones, thereby altering the epigenetic regulation of gene expression. The liver is the major organ within which methylation reactions occur, and many of the hepatic genes are involved in pathways for the development of fatty liver, hepatic fibrosis, and hepatocarcinomas are epigenetically regulated (Mehedint MG and Zeisel SH, 2013).
The effect of choline on preventing fatty liver has been evident for some time. Research published in 1958 reported the positive effects of choline on liver health. A single dose of choline administered to choline-deficient animals increases the oxidation of liver fat as well as the synthesis of liver phosphatide P32 (Zilversmit et al, 1958).
NAFLD affects one-third of U.S. adults; one-half of obese men; and 11% of adolescents. One in 10 have liver disease.
2012 sales of liver/detox supplements topped $111 million in 2012, up 95.7% vs. 2011.
Obesity, Rx medications, especially statins, and alcohol consumption along with high incidence of cirrhosis of the liver, especially in Europe, will continue to draw attention to liver health. Canada, the EU, and the UK published government warning reports on liver health in 2013. Alcohol consumption in the U.S. is at an all-time high.
References:
Corbin KD and Zeisel SH (2012) Curr Opin Gastroenterol March 28(2):159-165.
Mehedint MG and Zeisel SH (2013) Choline's role in maintaining liver function: new evidence for epigenetic mechanisms. Curr Opin Clin Nutr Met Care 16(3):339-45.
Zilversmit DB and Diluzio NR (1958) The role of choline in the turnover of phospholipids. Am J Clin Nutr 6(3):235-41.