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Probably changing the way we think, fat in the liver seems to be of grave concern than it actually thought. The latest study from the Washington University School of Medicine in St. Louis claimed that it’s not whether body fat is accumulated in the belly that affects metabolic threat factors for diabetes, high blood triglycerides and cardiovascular disease but whether it is gathered in the liver.

Nonalcoholic fatty liver disease is having too much liver fat. Experts report that when fat accumulates in the liver, people undergo serious metabolic problems such as insulin resistance, which affects the body’s capacity to metabolize sugar. They also have a rise in production of fat particles in the liver that are secreted into the bloodstream and supposedly increase the level of triglycerides.

The scientists have observed over the years that the body fat in an individual apparently controls their metabolic and cardiovascular risk. Apparently increased risk of diabetes and heart disease is connected to increased fat within the belly called as visceral fat.

Senior investigator Samuel Klein, M.D commented “Data from a large number of studies shows that visceral fat is associated with metabolic risk, which has led to the belief that visceral fat might even cause metabolic dysfunction. However, visceral fat tracks closely with liver fat. We have found that excess fat in the liver, not visceral fat, is a key marker of metabolic dysfunction. Visceral fat might simply be an innocent bystander that is associated with liver fat.”

Klein, the Danforth Professor of Medicine and Nutritional Science, directs the Division of Geriatrics and Nutritional Science and the Center for Applied Research Studies, as well as Washington University’s Center for Human Nutrition. He is of the opinion that most of our body fat known as subcutaneous fat is apparently placed under our skin. But approximately about 10 percent is present inside the stomach and much smaller amounts are within organs such as the liver and muscle.

An elevated and normal amount of liver fat was compared in obese people. Apparently age, sex, body mass index, percent body fat and degree of obesity was matched in all the subjects. Klein’s team determined that surplus fat inside the liver classifies those people who are at threat for metabolic problems and this was done after carefully evaluating the different amounts of visceral fat or liver fat in obese people.

Elisa Fabbrini, M.D., Ph.D., assistant professor of medicine commented “We don’t know exactly why some fats, particularly triglycerides, will accumulate inside the liver and muscle in some people but not in others. But our data suggest that a protein called CD36, which controls the transport of fatty acids from the bloodstream into different tissues, is involved.”

Fatty acids are the building blocks for making fats called as triglycerides. T. Klein, Fabbrini and their colleagues discovered that apparently among people with elevated liver fat, CD36 levels were lower in fat tissue and higher in muscle tissue.

For changing it into triglyceride, Fabbrini and Klein believe that changes in CD36 could be accounted for deflecting circulating fatty acids away from fat tissue and into liver and muscle tissue. For metabolic dysfunction, increased tissue uptake of fatty acids could be responsible.

Klein commented “Fatty liver disease is completely reversible. If you lose a small amount of weight, you can markedly reduce the fat content in your liver. In fact, even two days of calorie restriction can cause a large reduction in liver fat and improvement in liver insulin sensitivity.”

Klein believes that people who are obese should be encouraged to lose weight but don’t seem to have high levels of fat in the liver. Such individuals are apparently people are at a risk for heart disease and diabetes, which have an elevated liver fat. He mentioned that loosing some pounds could make a huge difference so they needed to be treated aggressively.

This study was published online in the journal PNAS Early Edition.