Low-fat or low-carb? Gene test claims to show which diet works best; skeptics aren’t so sure

Gene test claims to show what diet works best

Researchers say a gene test may help predict whether you can lose more weight on a low-fat or a low-carb diet.

It looks at three genes that affect how foods are metabolized. In a small study, women who were on diets matched to their genetic makeup lost up to five times more weight than women on diets not ideally matched to their genes.

Some scientists say the test itself needs more testing before it can be recommended. For now, they say dieters should focus on sensible eating and exercise, and not regaining the pounds they do manage to lose. The test costs $149 and is sold by a Massachusetts company, Interleukin Genetics Inc.