Forms of intermittent fasting and calorie restriction are quite effective at reducing inflammation, and the work done on fasting mimicking diets has gone a long way towards quantifying this effect. The goal was to find the 80/20 point on the line between mild calorie restriction and fasting, the most food one can eat and still obtain lasting benefits to metabolic health due to the usual reaction to an extended period of restricted calorie intake. (Which, per that research, is one day at 1000 kcal followed by four more days at 750 kcal per day, provided those calories are in the form of healthy food). Since lowered calorie intake has anti-inflammatory effects, it isn't surprising to see researchers investigating it in the context of inflammatory diseases. The work here is largely interesting for the continued focus on the degree to which the benefits of fasting emerge during the period of increased calorie intake afterwards, rather than during the fast.
A new study reports on the health benefits of periodic cycles of the diet for people with inflammation and indicated that the diet reversed inflammatory bowel disease (IBD) pathology in mice. Results showed that fasting-mimicking diet caused a reduction in intestinal inflammation and an increase in intestinal stem cells in part by promoting the expansion of beneficial gut microbiota. Study authors say the reversal of IBD pathology in mice, together with its anti-inflammatory effects demonstrated in a human clinical trial, indicate that the regimen has the potential to mitigate IBD.
For people with a poor diet, a "once in a while" fix is the periodic use of a low-calorie, plant-based diet that causes cells to act like the body is fasting. Earlier clinical trials allowed participants to consume between 750 and 1,100 calories per day over a five-day period and contained specific proportions of proteins, fats, and carbohydrates. Participants saw reduced risk factors for many life-threatening diseases. "We know that the fasting-mimicking diet is safer and easier than water-only fasting, but the big surprise from this study is that if you replace the fasting-mimicking diet, which includes pre-biotic ingredients, with water, we don't see the same benefits."
In the study, one group of mice adhered to a four-day fasting-mimicking diet by consuming approximately 50 percent of their normal caloric intake on the first day and 10 percent of their normal caloric intake from the second through fourth days. Another group fasted with a water-only diet for 48 hours. The study demonstrated that two cycles of a four-day fasting-mimicking diet followed by a normal diet appeared to be enough to mitigate some, and reverse other, IBD-associated pathologies or symptoms. In contrast, water-only fasting came up short, indicating that certain nutrients in the fasting-mimicking diet contribute to the microbial and anti-inflammatory changes necessary to maximize the effects of the fasting regimen.
The research team observed activation of stem cells and a regenerative effort in the colon and the small intestine, which increased significantly in length only in the presence of multiple cycles of the fasting-mimicking diet. They concluded that fasting primes the body for improvement, but it is the "re-feeding" that provides the opportunity to rebuild cells and tissues. "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. The ingredients in the diet pushed the microbes to help the fasting maximize the benefits against IBD."