Calorie restriction may slow aging by taming immune protein C3
In the NIH CALERIE trial, adults cutting calories by about 11–14% for two years showed a drop in the immune protein C3 in plasma. The study traced C3 back to age-related white adipose tissue, produced mainly by age-associated macrophages, and found that lowering C3 might reduce chronic inflammation linked to aging. In mice, pharmacologically inhibiting C3 decreased age-related inflammation, suggesting that the benefits of calorie restriction could be mimicked without weight loss. Researchers are now evaluating FDA-approved C3 inhibitors as a potential way to extend healthy lifespan while preserving immune function.