Researchers have identified a potential new mechanism by which fasting may help reduce inflammation, a potentially damaging side-effect of the body’s immune system which is at the root of some chronic diseases. The study offers insights into the health benefits of calorie restriction.
Researchers have known for some time that high-calorie Western diets increase the risk for obesity, type 2 diabetes, and heart disease, which are linked to chronic inflammation. They’ve also known that fasting, or restricting food intake, can help reduce inflammation, but the reasons why are unclear. To help answer this question, a group of scientists studied blood samples from 21 volunteers who ate a meal and then fasted for 24 hours before consuming a second meal containing the same amount of calories.
The scientists found that fasting increased levels of a chemical in the blood called arachidonic acid, which is known to inhibit inflammation. In further studies using immune cells cultured in the lab, they showed that arachidonic acid turns down the activity the NLRP3 inflammasome, a protein structure that helps trigger inflammation to help protect the body when it senses damage and plays a role in fighting diseases. The findings also suggest that regular fasting over a long period could help reduce chronic inflammation associated with certain diseases, they said. The findings may also help explain some of the beneficial effects of non-steroidal anti-inflammatory drugs such as aspirin, they said. Aspirin may prevent the breakdown of arachidonic acid, causing it to increase and reduce inflammation, the researchers suggested.
Their study, partly funded by NHLBI, appears in the journal Cell Reports.