Calorie shifting diet versus calorie restriction diet: a comparative clinical trial study.
BACKGROUND
Finding new tolerable methods in weight loss has largely been an issue of interest for specialists. Present study compared a novel method of calorie shifting diet (CSD) with classic calorie restriction (CR) on weight loss in overweight and obese subjects.


METHODS
Seventy-four subjects (body mass index ≥25; 37) were randomized to 4 weeks control diet, 6 weeks CSD or CR diets, and 4 weeks follow-up period. CSD consisted of three phases each lasts for 2 weeks, 11 days calorie restriction which included four meals every day, and 4 h fasting between meals follow with 3 days self-selecting diet. CR subjects receive determined low calorie diet. Anthropometric and metabolic measures were assessed at different time points in the study.


RESULTS
Four weeks after treatment, significant weight, and fat loss started (6.02 and 5.15 kg) and continued for 1 month of follow-up (5.24 and 4.3 kg), which was correlated to the restricted energy intake (P < 0.05). During three CSD phases, resting metabolic rate tended to remain unchanged. The decrease in plasma glucose, total cholesterol, and triacylglycerol were greater among subjects on the CSD diet (P < 0.05). Feeling of hunger decreased and satisfaction increased among those on the CSD diet after 4 weeks (P < 0.05).


CONCLUSIONS
The CSD diet was associated with a greater improvement in some anthropometric measures, Adherence was better among CSD subjects. Longer and larger studies are required to determine the long-term safety and efficacy of CSD diet.
Department of Clinical Nutrition and Dietetic, National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Sayed Hossein
SH
Davoodi
Department of Food and Nutrition Policy and Planning Research, National Nutrition and Food Technology Research Institute, Faculty of Nutrition and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Marjan
M
Ajami
Department of Pharmacognosy, Phytochemistry Research Center, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Seyyed Abdulmajid
SA
Ayatollahi
Medical School, Islamic Azad University, Najafabad, Isfahan, Iran.
Kamran
K
Dowlatshahi
Department of Nutrition, School of Health, Iran University of Medical Sciences, Tehran, Iran.
Gholamali
G
Javedan
Department Physiology and Physiology Research Center, Iran University of Medical Sciences and Nano Vichar Pharmaceutical Ltd, Tehran, Iran.
Hamid Reza
HR
Pazoki-Toroudi
Calorie shifting diet; calorie restriction diet; obesity; resting metabolic rate; weight loss