Investigating the effects of negative-calorie diet compared with low-calorie diet under exercise conditions on weight loss and lipid profile in overweight/obese middle-aged and older men

Background/aim: Negative-calorie diets (NCDs) are among the popular dieting guides for weight loss; however, there is still little knowledge about this method. The present study aimed to determine the effects of a NCD supplemented with exercise on weight loss and lipid profile, and to compare its efficiency with low-calorie diets (LCDs) with exercise among elderly adult men with abnormal weight gain. Materials and methods: Participants included sedentary men (aged 45-75 years) who were overweight or obese (n = 37). They were randomly divided into 2 groups: a group with a NCD and exercise, and a group with a LCD with exercise. Of all 37 participants, 30 completed the treatment. Weight assessment parameters, including changes in weight and body composition and blood sample tests, were performed before and 3 months after intervention. Results: All parameters decreased significantly in both groups. Elevation in high-density lipoprotein (HDL) cholesterol levels (P < 0.001) was different between the 2 groups. The decline in the total cholesterol to HDL cholesterol ratio was greater in the LCD than the NCD group. Conclusion: Contrary to expectations, both weight-loss diets were equally efficacious.