Switching from a High-Fat to a Regular Chow Diet Improves Obesity Progression in Mice

The fast-paced lifestyle of modern people has changed their dietary structure and increased the prevalence of obesity, of which a high-fat diet is the main cause. Therefore, this study investigates whether reducing fat intake can improve obesity and physical health. We induced an obese model with a 60 kcal% fat diet (HFD) for 12 weeks, followed by an intervention with a 4.9 kcal% fat diet (regular chow diet, RD) for 20 weeks. We found that after 20 weeks of RD, various indicators were significantly reduced compared with the HFD group, including dietary intake (3.26 ± 0.38 g, p < 0.01), Lee index (385.24 ± 14.22, p < 0.0001), blood glucose (8.75 ± 2.44 mmol/L, p < 0.01), blood lipids (TC: 2.60 ± 0.63 mmol/L, p < 0.001; TG: 0.72 ± 0.08 mmol/L, p < 0.001; and LDL-C: 0.57 ± 0.30 mmol/L, p < 0.0001), and inflammatory status (IL-6: 32.70 ± 7.55 pg/mL, p < 0.05). In addition, increasing dietary intake also indirectly increased fiber intake, which could promote intestinal microbiota diversity. Changing the diet of obese mice from HFD to RD still maintained the abundance of the probiotics Akkermansia, Parabacteroides, Alloprevotella, and Porphyromonadaceae, among which fiber intake played an important role. Therefore, we found that only reducing dietary fat intake was effective for weight loss, and dietary fiber intake helped maintain a healthy intestinal microbiota balance.