According to the research on mouse models conducted by the Icahn Medical College in Mount Sinai, USA, fasting may not be beneficial to resist infection and may lead to an increase in the risk of heart disease. The study, published in the journal Immunology on February 23, may help people better understand the impact of long-term fasting on the body. In order to better understand how fasting affects the immune system, researchers analyzed two groups of mice. One group ate breakfast immediately after waking up, which was the most abundant meal of their day, while the other group did not eat breakfast. The researchers collected baseline blood samples of the two groups of mice when they woke up, and collected them again after 4 hours and 8 hours, respectively. During the blood test, the researchers noticed that the number of mononuclear cells in the fasting group was significantly different. Monocytes are white blood cells that are produced in the bone marrow and spread in the body. They play many key roles in the body and can fight infection, heart disease and even cancer. At baseline, all mice had the same number of monocytes. However, after 4 hours, the monocytes of mice in the fasting group were significantly affected, and 90% of these cells disappeared from the blood. This number further decreased after 8 hours. At the same time, mononuclear cells in the non-fasting group were not affected. In fasting mice, researchers found that monocytes returned to the bone marrow and entered a dormant state. At the same time, the production of new cells in bone marrow decreased. The researchers continued to fast the rats for 24 hours and then refed. The cells hidden in the bone marrow returned to the blood within a few hours, which led to the intensification of inflammation. These altered monocytes can not prevent infection, but are more inflammatory and have lower resistance to infection. Researchers say there is sufficient evidence to prove the benefits of fasting, but like many things in life, balance is very important. Therefore, to some extent, the beneficial things may have unexpected negative effects in another aspect. (Xinhua News Agency)