A new study published in Nature Communications on August 13, 2026, reveals that a protein in the brain called CD44 plays a key role in regulating fat intake and obesity. Researchers at the University of California, Irvine, found that mice lacking the CD44 gene in their brain showed a strong preference for high-fat foods and became obese even on a normal diet.
The study, led by Dr. Robert Mahley, showed that CD44 normally acts as a brake on fat consumption. When the protein is absent or impaired, the brain's reward system becomes hypersensitive to dietary fat, driving overeating and weight gain. The findings were confirmed through a series of experiments involving genetic knockout mice and behavioral tests.
This discovery could lead to new treatments for obesity by targeting CD44 or its downstream pathways. The researchers note that while the study was conducted in mice, the same protein exists in humans, offering a promising avenue for future drug development. However, they caution that more research is needed before clinical applications.
The study adds to a growing body of evidence linking brain mechanisms to dietary choices and obesity, which affects over 650 million adults worldwide according to the World Health Organization.
