A new meta-analysis of 23 trials reveals that reducing carbohydrate intake to below 45% of daily energy may yield small weight loss and risk marker improvements for adults with overweight or obesity, but the benefits are limited and vary with diet intensity.
A new meta-analysis suggests that cutting carbohydrate intake can deliver modest benefits for adults with overweight or obesity, but the gains appear to be limited rather than dramatic. Researchers reviewing 23 randomised controlled trials found that diets with carbohydrates making up less than 45% of daily energy intake were linked to small reductions in body weight and some measures tied to cardiometabolic risk.
The analysis, published in the Journal of the Academy of Nutrition and Dietetics and led by Matthew Landry at the University of California, Irvine, pooled evidence from studies published between 2010 and 2025. Most of the trials compared moderately carbohydrate-restricted diets with higher-carbohydrate eating patterns, and intervention lengths ranged from 4 weeks to 36 months. The review focused on adults with overweight or obesity and no other established disease.
Compared with higher-carbohydrate diets, carbohydrate restriction was associated with an average weight loss of 1.32 kg, along with small improvements in waist circumference and fat mass. The review also found reductions in A1c, triglycerides and systolic blood pressure, while fasting blood glucose improved only slightly. There was no clear effect on total cholesterol, LDL cholesterol or HDL cholesterol. The researchers said the size of the carbohydrate cut within the range studied did not appear to change the results meaningfully.
The findings fit with earlier research showing that lower-carbohydrate diets can help with short-term weight loss, although the broader cardiometabolic picture has been mixed. Previous meta-analyses have also reported benefits for blood pressure and triglycerides, but some have found rises in total cholesterol or LDL cholesterol, especially with very-low-carbohydrate plans. The new review adds to the evidence that carbohydrate restriction may help some people lose a little weight and improve selected risk markers, but it does not suggest a clear advantage for extreme carbohydrate cutting over more moderate restriction.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
