Calorie restriction fights aging via one blood protein
Eating less slows ageing, but very few people manage to sustain it. Researchers have now identified a specific blood molecule responsible for the anti-inflammatory effect of calorie restriction. In mice, they triggered the same effect without any dieting at all.
Chronic, low-grade inflammation is one of the central mechanisms by which the body ages. As people get older, this background inflammation gradually increases. It contributes to conditions such as cardiovascular disease, type 2 diabetes, and cognitive decline. Calorie restriction (eating less than usual, without malnutrition) is one of the few interventions that has consistently extended lifespan in animal studies. But exactly how it works has only been partly understood.
The researchers focused on an immune protein called C3, a component of the complement system (a branch of the immune system that normally fights infections). With moderate calorie restriction, C3 levels in the blood fell. Lower C3 corresponded with less chronic inflammation. The researchers then blocked C3 directly in mice, without reducing the animals’ food intake. That also reduced age-related inflammation.
A shortcut to the same effect?
That result raises the possibility that future treatments could mimic the anti-inflammatory benefits of calorie restriction without requiring people to eat drastically less. That would be of practical importance, because strict calorie restriction is not sustainable for most people over the long term.
Important caveats remain
This is mouse research. It is not yet known whether the same pathway works in humans, whether blocking C3 is safe in the long term, or whether the effects are comparable to genuine calorie restriction. The complement system also plays a role in fighting infections, so interfering with it requires careful investigation of potential side effects. The researchers describe this as a possible starting point for future treatments, not a proven strategy. That said, the result offers a concrete mechanism that justifies further investigation.
Terms to search for yourself: caloric restriction inflammaging, complement system C3 aging, chronic low-grade inflammation intervention