Soy protein reduces fatty liver toxicity and insulin resistance

The September 2005 issue of Journal of Lipid Research published the findings of research showing that a diet rich in soy protein helps protect against hepatic steatosis (fatty liver). Fatty liver disease is characterized by an increased production of fatty acids in the liver. The condition is associated with the development of insulin resistance, and can result in liver enlargement and chronic liver disease. There is currently no treatment for this potentially fatal condition.

For 160 days, researchers fed soy protein diets to rats bred to develop diabetes and fatty liver. Although the rats developed obesity and hyperinsulinemia as expected, they failed to exhibit an accumulation of cholesterol and triglycerides in their livers. The effects of the soy diet appeared to be due to a low expression of genes involved in the synthesis of fatty acids and triglycerides in the liver. Additionally, the soy-rich diet also increased the breakdown of fatty acids in the liver, further lowering the accumulation of fat in the liver.

Although more research is needed on the subject, researchers believe the results indicate that consumption of soy protein could reduce insulin resistance and its resulting damage to the liver and kidneys.

J Lipid Res. 2005 Sep;46(9):1823-32