We’re back to talking about intermittent fasting. The latest to come under the media spotlight for this dietary practice is the UK prime minister, Rishi Sunakwho would observe the pattern of abstaining from food for 36 hours a week.
But what does science say about fasting? It came out just now a new study which investigates its potential protective effect. It was signed by a group of British scientists from the University of Cambridge, with US colleagues.
by Giulia Masoero Regis
The authors of the work, published on ‘Cell Reports’, explain that they may have discovered a new way in which fasting helps reduce inflammation, a potentially harmful side effect of the immune system that underlies a number of chronic diseases. In the research, the team explains that this eating pattern increases the levels of a chemical in the blood known as arachidonic acid, which inhibits inflammation, in fact. For researchers, this could also help explain some of the beneficial effects of drugs like aspirin. It has long been known in the scientific community that the diet you eat – particularly a high-calorie Western diet – can increase your risk of conditions, including obesity, type 2 diabetes and heart disease, linked to chronic inflammation.
The mechanism of inflammation
Inflammation is the body’s natural response to injury or infection, but this process can be triggered by other mechanisms, including the so-calledinflammasome‘, which acts as an alarm within cells, triggering inflammation to help protect our body when it senses damage. But the inflammasome can ‘switch on’ inflammation involuntarily: one of its functions is to destroy unwanted cells, which can result in the cell’s contents being released into the body, where it triggers inflammation.
“This has become evident in recent years – he explains Clare Bryant of the Department of Medicine at Cambridge University – is that an inflammasome in particular, Nlrp3is very important in a series of diseases such as obesity and atherosclerosis, but also Alzheimer’s and Parkinson’s, pathologies of older people, particularly in the Western world.”
Fasting may help reduce inflammation, but the reason is still unclear, scientists point out. To help answer this question, the team led by Bryant and colleagues from the University of Cambridge and the National Institutes of Health (Nih) in the States studied blood samples from a group of 21 volunteers, who ate a 500-gram meal. kcal and then fasted for 24 hours before eating a second 500kcal meal.
Arachidonic acid ‘turns off’ inflammation
The team found that limiting calorie intake increased levels of a lipid known as arachidonic acid. Lipids are molecules that play important roles such as storing energy and transmitting information between cells. As people resumed eating, arachidonic acid levels decreased. When the researchers studied the effect of arachidonic acid in immune cells grown in the laboratory, they found that it reduces the activity of the Nlrp3 inflammasome. An observation that surprised the team as arachidonic acid was previously thought to be linked to increased levels of inflammation, not a decrease.
by Elvira Naselli
The hopes: understand if it also works against Alzheimer’s and Parkinson’s
This, Bryant reasons, “provides a potential explanation that changing our diet – particularly through fasting – protects us from inflammation, or rather the harmful form that underlies many high-calorie diseases.” Western eating habits. “It’s too early to say whether fasting protects against diseases like Alzheimer’s and Parkinson’s because the effects of arachidonic acid are only short-lived, but the work adds to a growing body of scientific literature on the benefits of calorie restriction. And it suggests that Regular fasting over a long period could help reduce the chronic inflammation we associate with these conditions. It’s certainly an attractive idea.”
The analogies with aspirin
The findings also suggest a mechanism by which a high-calorie diet might increase the risk of these diseases. Studies have shown that some patients who eat a high-fat diet have increased levels of inflammasome activity. “There may be a yin and yang effect going on here,” Bryant illustrates. And “arachidonic acid may be one way that this is happening.” For researchers, the discovery could also offer clues to an unexpected way in which so-called nonsteroidal anti-inflammatory drugs such as aspirin work.
Normally, arachidonic acid is rapidly broken down in the body, but aspirin blocks this process, which can lead to increased levels of arachidonic acid, which in turn reduces inflammasome activity and therefore inflammation.