Your genes may decide whether a low-carb diet sends cholesterol soaring

Low-carb diets have become popular, but their impact on cholesterol varies among individuals. New research suggests genetic factors may explain why some people experience a rise in LDL cholesterol, a heart disease risk factor, while others do not. A study presented at NUTRITION 2026 by Alexa Barad, PhD, RDN, indicates that certain genetic profiles can make individuals more sensitive to the LDL cholesterol-raising effects of saturated fat in low-carb diets.

This genetic influence could explain why two people following similar diets can have different cholesterol responses. The study, based on data from the DIETFITS trial involving over 600 adults, found that those on a low-carb diet with a genetic predisposition to higher LDL cholesterol were more likely to see an increase when consuming more saturated fat.

Barad emphasizes the importance of monitoring individual responses to dietary changes rather than assuming a one-size-fits-all approach. The researchers used a polygenic score, combining thousands of genetic variants, to estimate each participant's overall genetic tendency toward higher or lower LDL cholesterol. While genetic testing is not necessary to apply the findings, people should pay attention to how their bodies respond to dietary changes.

The study suggests focusing on unsaturated fats like those found in nuts, seeds, olive oil, and avocado, especially for those following low-carb diets, to lower the risk of unfavorable cholesterol changes.