Why Weight Loss Can Be Difficult
A recent study has uncovered why losing weight can be so difficult for obese individuals. Researchers at the University of California, San Diego, found that neutrophils—a type of white blood cell—actively slow down fat loss. This discovery, published in Nature, reveals a previously unknown immune response that may explain why diets often fail.
Neutrophils move into fatty tissue, particularly visceral white fat—the most harmful but hardest to lose. When triggered by stress like food deprivation or cold, they release signalling molecules, including interleukin-1-beta. These molecules help the body conserve energy by slowing fat breakdown.
In obese individuals, the genes linked to this pathway are far more active. This suggests their immune systems work harder to prevent fat loss. Tests in mice showed that blocking this neutrophil mechanism led to more effective weight reduction. The findings add to a growing list of factors that make weight loss challenging. Alongside changes in the brain, gut microbiome, and fat cells, this immune response further complicates efforts to shed excess weight.
This breakthrough could pave the way for new obesity treatments. By targeting the neutrophil pathway, future therapies might make fat loss more achievable. The study also highlights why traditional dieting often falls short for those with obesity.
