In the on-going battle over dairy products, which often appears to be an ideological one centered on whether humans should be consuming milk from cows or any other animal at all, a new study has examined data from an ongoing study of more than 40,000 male doctors, pharmacists and other health professionals.

The study, which is led by doctors at Massachusetts General Hospital, the Harvard Medical School and the Harvard School of Public Health arrived at the conclusion that regular consumption of low-fat dairy products such as skim milk or low-fat yogurt, slightly decreases a man's risk of developing type II diabetes.

The effect though modest was consistent whether or not study participants were physically active, overweight or had a family history of diabetes.

Previous studies have shown that low-fat dairy products, as part of a diet that's rich in fruits and vegetables, also helps to reduce high blood pressure.

The latest study is published in the Archives of Internal Medicine.

The paradox says Semenkovich, was that when they inactivated fatty-acid synthase in the liver and eliminated fat in the diet, the animals became sick, with livers full of fat.

Further examination also found that, in the absence of new fat, the mice exhibited a marked decline in the activity of genes critical for the metabolism of glucose, fatty acids, and cholesterol, genes which are normally targeted by PPARa, a key energy management gene activated by fatty acids.

"In short", says Semenkovich "all fatty acids are not created equal, at least not in the liver".

In conclusion, say the researchers, it suggests that products of fatty acid synthesis regulate glucose, lipid, and cholesterol metabolism by activating distinct pools of PPARa in the liver, but further study will be needed to elucidate the mechanism by which nutrient sensors in the body distinguish between different sources of fat.

The study is published in the May issue of Cell Metabolism.

cellpress/