Calorie restriction (CR) has been commonly recognized as the best means to improve metabolic health and extend lifespan. However, it is difficult to carry on continuous CR in practice.

The concept of intermittent CR has been proposed in recent years, that is, to reduce calorie intake for a short period of time and then restore normal diet.

To investigate whether intermittent CR can effectively prevent the progression of diabetes, Prof. CHEN Yan’s group at Shanghai Institute of Nutrition and Health of Chinese Academy of Sciences conducted a study which suggests that caloric restriction, especially intermittent caloric restriction or intermittent amino acid restriction, is an effective nutritional intervention for diabetes. The finding was published in Nutrition & Metabolism.

Researchers used db/db mice as a model of type 2 diabetes mellitus to analyze the effect of intermittent CR on prevention of diabetes, and used a "fasting-mimicking diet" (FMD) which is a low-carbohydrate, low-protein, and high-fiber food rich in a variety of plant ingredients to intermittently limit calorie intake in mice.

The mice were fed low-calorie FMD for one week (30% of the calorie intake of the control group), and then resumed normal chow for one week. The program was lasted for eight weeks.

It was found that intermittent administration of the FMD significantly reduced fasting blood glucose, improved glucose tolerance and insulin sensitivity, increased the number of insulin-secreting beta cells in islets, and increased the expression of Ngn3, a marker of stem cells in beta cells, suggesting that FMD can effectively interfere with the progression of type 2 diabetes. 

Also, the results showed that the gut microbiota of the mice changed significantly after FMD treatment, and some of the changes were associated with the interventional effect of diabetes.

Moreover, PhD student AN Ruomei analyzed the interventional effect of the FMD on type 1 diabetes mellitus.

The study established type 1 diabetes model in mice by injecting a drug (STZ) to destroy islet beta cells. It was found that intermittent use of the FMD could significantly reduce fasting blood glucose and increase the number of islet beta cells, suggesting that intermittent caloric restriction also functioned in preventing type 1 diabetes mellitus.

This research was supported by grants from the National Natural Science Foundation of China, the Ministry of Science and Technology of China, and the Chinese Academy of Sciences.