TOPLINE:

A combined low-carbohydrate diet and resistance training program leads to significant weight loss in Japanese participants, regardless of their genetic risk score (GRS). An efficiency score, which integrates GRS with baseline BMI and body fat percentage, predicts short-term weight-loss outcomes more accurately than GRS alone.

METHODOLOGY:

• It remains unclear whether GRS can predict response to obesity interventions such as diet and exercise, particularly in non-European populations.
• Researchers analyzed the relationship between Japanese-specific GRS and weight-loss outcomes in Japanese participants who completed an 8- to 12-week intervention combining a low-carbohydrate diet with resistance training.
• Participants followed a structured dietary protocol targeting approximately 50 g/day of carbohydrates and 1-2 g of protein per kg of body weight, with no specific restrictions on fat intake; resistance training consisted of 16 supervised sessions over the intervention period, with participants attending one to two 50-minute sessions per week.
• GRS was calculated from 75 single-nucleotide polymorphisms identified in a prior Japanese genome-wide association study.
• An efficiency score incorporating GRS, baseline BMI, and body fat percentage was calculated to assess its predictive value for intervention outcomes.

TAKEAWAY:

• The study included 145 participants (mean age, 46.0 years; 16.6% male).
• Mean BMI decreased significantly across the cohort, from 27.6 at baseline to 23.8 post-intervention (P < .001).
• At baseline, GRS was significantly correlated with BMI (correlation coefficient [r], 0.23; P = .0063) and body fat percentage (r, 0.26; P = .0014).
• Efficiency scores demonstrated a stronger predictive value for changes in BMI and body fat percentage (variance [adjusted R²], 34.3% and 8.0%, respectively; P < .001) than GRS alone (adjusted R², 1.8%; P = .086 and adjusted R², 1.7%; P = .051, respectively).

IN PRACTICE:

“The effectiveness of our combined diet and exercise program across different GRS values indicates that an individual’s genetic constitution should not be considered a hindrance to weight loss,” the authors wrote. 

SOURCE:

The study was led by Sho Nakamura, Graduate School of Health Innovation, Kanagawa University of Human Services, Kawasaki, Japan. It was published online in Obesity.

LIMITATIONS:

The historical cohort design without a control group limited the ability to attribute weight loss solely to the intervention. Participants were paying clients in a specific commercial weight management program, potentially limiting generalizability. Quantitative adherence data for dietary and exercise protocols were not systematically collected. 

DISCLOSURES:

The study was supported by a grant from the Japan Society for the Promotion of Science. The authors reported having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.