Low-Calorie May be Better than No-Calorie Fasting for Inflammation Reduction

Results of a new study show that a low-calorie, fasting-mimicking diet can reduce intestinal inflammation and increase intestinal stem cells to repair the gut. The study, published recently in Cell Reports, claims that this type of diet provides greater benefits than no-calorie, water fasting diet for reversing inflammation and inflammatory bowel disease (IBD).

The study was performed by researchers at the University of California (USC) Longevity Institute. Their research combined two interventions that are conventionally studied separately: the first is what should be eaten daily and the second is the effects of fasting. The fasting-mimicking diet involves cycles of calorie restriction, with attention paid to the balance of foods and nutrients that are consumed during that period.

For the study, the researchers observed two groups of mice. The first group was fed a fasting-mimicking diet for four days. These mice consumed approximately 50% of their normal caloric intake on the first day and 10% of their normal caloric intake on the remaining three days. The calories consumed mimicked a human diet of vegetables, fruits, olive oil, vitamins, and minerals. The second group of mice followed a water-only fasting diet for 48 hours.

The study demonstrated that two cycles of the four-day fasting-mimicking diet followed by a normal diet appeared to mitigate some IBD-associated pathologies or symptoms and even reverse others. These effects were greater than what was seen in the water-only fasting diet, indicating that nutrients in the former diet contribute to some of the microbial and anti-inflammatory changes.  

The team also observed activation of stem cells and a regenerative effort in the colon and small intestine that increased in length in the presence of multiple cycles of the fasting-mimicking diet. Combined with evidence obtained from previous studies on the benefits of a fasting-mimicking diet to reduce inflammation in human subjects, the researchers believe these findings offer strong support for the ability of such cycles to improve healing and reduce IBD symptoms.

"We've determined that the dietary components are contributing to the beneficial effects; it's not just about the cells of the human body but it's also about the microbes that are affected by both the fasting and the diet," said study author Valter Longo. "The ingredients in the diet pushed the microbes to help the fasting maximize the benefits against IBD."