Plant-based caloric restriction diets versus conventional calorie-restricted diets for weight loss and metabolic health in obese adults: a 12-week randomized, open-label, non-inferiority trial

Background: Plant-based caloric restriction diet (PB-CRD), combining plant-based nutrition with intermittent caloric restriction, represent a structured dietary strategy to obesity management. This study compared the effects of PB-CRD and calorie-restricted diet (CRD) on weight loss, and metabolic health, hypothesizing that PB-CRD is non-inferior to CRD for weight loss. Methods: , age: 18-45 years) were randomized in a 1:1 ratio to either a PB-CRD ('5 + 2' pattern: 5 days/week of provided standardized plant-based meals and 2 days/week of self-selected meals within prescribed caloric targets) or a CRD (7 days/week of self-selected meals within prescribed caloric targets). Both groups adhered to the same daily energy intake targets of 1,600 kcal/day (men) and 1,300 kcal/day (women). The primary outcome was weight loss, while secondary outcomes included body composition, glucose and lipid metabolism, liver and kidney function, oxidative stress, and inflammation markers. Results: < 0.05), with no substantial differences between groups. Conclusion: Both PB-CRD and CRD were effective for weight loss, with PB-CRD demonstrating non-inferiority. Furthermore, PB-CRD offered superior benefits in reducing total body fat and improving uric acid metabolism, while improving insulin sensitivity and liver function in adults with obesity. Clinical trial registration: Identifier ChiCTR1800015156.