Our immune system, which provides vital protection to our bodies, provides crucial protection in the conflicts we experience as inflammation, calling chemical agents and cellular assassins to the sites of damage.
Unfortunately, various factors can cause inflammation to go wrong, leaving a trail of side effects. For example, adhering to a high-calorie Western-type diet increases the risk of an inflammatory syndrome that underlies various health conditions.
Previous research has shown that fasting can protect against inflammation, so a team of researchers led by scientists from the University of Cambridge in the UK took a closer look at this relationship and how it occurs.
By examining blood samples from 21 volunteers, the researchers asked the volunteers to eat a 500-calorie meal, not eat for 24 hours, and then eat another 500-calorie meal, and determined that a compound called arachidonic acid increased due to starvation.
Arachidonic acid is a fat that has previously been associated with inflammation, but there were thoughts that arachidonic acid increased inflammation.
“This provides a potential explanation for how changing our diet – particularly by fasting – protects us from the harmful form of inflammation that underlies many diseases, particularly those linked to a Western-type high-calorie diet,” says immunologist Clare Bryant from the University of Cambridge.
The team conducted tests on cultured cells in the lab and found that arachidonic acid reduced the activity of a protein complex called the NLRP3 inflammasome.
Inflammasomes, as the name suggests, are mechanisms that trigger inflammation. Those like NLRP3 are like a kind of alarm bells for the immune system to act – in some cases overly aggressively and over a long period of time – and this is apparently how fasting keeps inflammation in check.
This reveals several interesting connections, not least that aspirin is also known to interact with NLRP3, and that the inflammasome is a mechanism that scientists want to question in relation to diseases such as Alzheimer’s.
“One thing that has emerged in recent years is that the NLRP3 inflammasome is very important in many important diseases, particularly obesity and atherosclerosis, but it’s also important in diseases like Alzheimer’s and Parkinson’s disease,” says Bryant.
Putting the pieces together, it is possible that fasting’s way of suppressing inflammation may ultimately protect against brain degeneration, but more research is needed to confirm the link.
“Because the effects of arachidonic acid are only short-lived, it is too early to say whether fasting protects against diseases such as Alzheimer’s and Parkinson’s, but our study adds to the growing body of scientific literature pointing to the health benefits of calorie restriction,” says Bryant.
The research has been published in Cell Reports.
