Comparison of three methods of intermittent fasting in high-fat-diet-induced obese mice.

Purpose: Intermittent fasting (IF), describes a variety of diets that the individual is exposed to intermittent periods of fasting and refeeding. The present study was designed to compare the three most popular intermittent fasting methods in high-fat-diet-induced obese mice. Methods: 50 male C57BL/6 mice were divided into Normal Control (CN), High-Fat Control (CH), IF1 (Alternate Day Fasting), IF2 (Time-Restricted Feeding), IF3 (5:2 Diet) diets. In the first phase of the study, the mice were fed ad libitum either with a 54% Calorie high-fat (CH, IF1, IF2, IF3) or standard CHOW (CN) for 8 weeks. Then, in the intervention phase, the IF groups were fasted for four weeks based on their fasting protocol. At the end of the study, the mice fasting blood, liver and fat tissue samples were biochemically and pathologically assessed. Results: The weight loss during the fasting period in IF1 and IF2 groups was significantly greater than CH. The epididymal fat pad weight was significantly lower in IF2 and IF3 compared to CH. The serum Triglyceride was significantly greater in CH than in the CN group. The tissue injury scores of the high-fat-diet groups were significantly greater than CN. Also, the tissue injury score was greater in IF1 group compared to the high-fat control group. Conclusion: All of the fasting protocols can prompt acceptable energy restriction and the ADF and TRF protocols can significantly cause weight loss. Also, the TRF and 5:2 Diets can lower the visceral adiposity. However further human studies focusing on dietary adherence seem necessary.