Where fat comes from determines whether the body can metabolize it effectively. Researchers at Washington University School of Medicine in St. Louis have found that the "old" fat stored in the body's peripheral tissues that is, around the stomach, thighs or butt cannot be "burned" efficiently unless "new" fat is obtained from the diet or synthesized in the liver. In once sense this is good news for those hoping to "lose weight" but without sacrificing some of the fatty foods we all enjoy.
The researchers found that an important fat-making enzyme found in the liver,
called Fatty Acid Synthase KnockOut in Liver (FASKOL), is essential for
making new fatty acids, which are needed to keep your sugar, fat, and cholesterol
levels healthy.
The effect of added dietary fat is also seen in lab mice lacking the FASKOL
enzyme who are treated
with a drug to activate a protein called PPAR-alpha. The researchers found
that liver fat fell back to normal in the mice in just ten days if they
were given this drug.
PPAR-alpha is found in all mammals, including humans, and is key to our metabolism
allowing us to extract energy from carbohydrates and
fats in our diet.
"Scientists have argued that PPAR-alpha is activated by fats," explains
team leader Clay Semenkovich, "But
we've never known which fats or where they come from. This study suggests
that new fat is a 'key' that unlocks the 'door' for PPAR-alpha in the
liver."
The liver is very important for processing nutrients consumed in the diet
and sending them on to the rest of the body. Abnormal processing of glucose
or lipids in the liver contributes to problems of type 2 diabetes and
atherosclerosis, and fatty liver disease often is seen in people who are
obese or suffer from insulin resistance. The liver is also thought to play a key role in
controlling the risk of heart disease.
The research team is now trying to identify which fats given in
small amounts could activate the PPAR-alpha. They also are studying
liver cells and fat cells to see how the liver can tell the difference
between old fat and new fat.
Semenkovich believes the findings could one day lead to a new way to treat obesity, type 2 diabetes and metabolic
disorders. For now, he says that dieters who want to lose fat stored in
peripheral tissues may find it useful to take in small amounts of dietary
fats, such as fish oils, that might more effectively activate PPAR-alpha and
fat burning pathways through the liver.
This research is only in the early stages and new treatments are yet to be
derived from it. However, it's never too late to take control of your own
metabolism and help reduce your risk of diabetes and other health problems
associated with being over weight by looking closely at your diet and the
amount of exercise you do.