Fat’s secret weapon?

BITING into a perfectly cooked French fry can be a taste of heaven, but what makes that fry so enticing? New research shows that the allure of greasy treats may come from a special sensor in your taste buds that’s tuned to fat.

Both animals and humans show a natural preference for fatty foods. But given that our taste buds are known to detect only five tastes -- salty, sweet, sour, bitter and umami, which is linked to the taste of meat and cheese -- scientists have wondered how we detect fatty foods.

Now Philippe Besnard and colleagues in Dijon, France, have shown that a protein found in the taste buds of rodents may be the elusive fat sensor. The scientists have discovered that when the protein comes in contact with fat on the tongue, it triggers release of stomach juices. Mice missing this protein don’t show the typical preference for fatty foods.

Humans also have this protein, although it’s not known if it’s found on the tongue. Scientists say the finding, published in the Nov. 1 issue of the Journal of Clinical Investigation, might shed light on some forms of obesity. Previous research suggests fatty foods are addictive and that obese people may have a stronger response to eating fat, says Nada Abumrad, a biochemist at the Washington University School of Medicine in St. Louis who wrote a commentary on the new findings.

“It’s possible that some people have a genetically determined preference for fat if they have higher levels of this protein in their taste buds,” Abumrad says. Knowing the exact structure of the protein might help researchers design fat substitutes or drugs that could alter levels of the protein on the tongue.