Attempts to lose weight more effectively by choosing food tailored to your genes may be a fruitless endeavor. So says an $8 million study into the concept.

The news: The study assigned 609 people to low-fat or low-carb diets. Analysis of whether those diets “matched” or “clashed” with a person’s supposed genetic predispositions showed no evidence that people on the “correct” diet lost more weight than others.

Dashed hopes: A smaller study by the same team in 2010 suggested DNA-tuned diets did work better than regular ones. But this larger, more powerful experiment suggests it may’ve been a false alert. “Let’s cut to the chase,” said Christopher Gardner, a coauthor of the study, to Stat. “We didn’t replicate that study; we didn’t even come close. This didn’t work.”

Why it matters: Consumer DNA testing is blowing up, and some companies offer insights into health, fitness, and nutrition based on what lurks inside your genes. This new study suggests that if you’re looking to lose weight, some genetic insights may not be very useful.