Dr David Cox reduces immune age by two years after dietary experiment
Updated
Updated · Evening Standard · Apr 22
Dr David Cox reduces immune age by two years after dietary experiment
3 articles · Updated · Evening Standard · Apr 22
After a two-month whole-food diet excluding ultra-processed foods, Dr Cox's immune age dropped by two years, with tests at Birmingham’s Queen Elizabeth Hospital showing halved inflammatory cells and doubled regulatory T cells.
The dietary changes included less saturated fat, more fibre, and omega-3 rich foods, which improved immune health by altering gut metabolites and reducing visceral fat that impairs the thymus.
Researchers suggest such dietary interventions may protect against immune ageing and related diseases, while plant polyphenols and positive stressors like exercise also contribute to healthier immune and cognitive ageing.
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IMM-AGE Test Reveals Dramatic Immune Age Reduction Following Ultra-Processed Food Elimination
Overview
In early 2026, Dr. David Cox transformed his diet by eliminating ultra-processed foods and focusing on whole foods rich in fiber and omega-3 fatty acids. This change reduced his visceral fat and boosted beneficial gut bacteria that produced anti-inflammatory short-chain fatty acids (SCFAs). These SCFAs, along with omega-3s, inhibited inflammatory pathways and strengthened the gut barrier, promoting regulatory T cells that calm inflammation. As a result, inflammatory immune cells nearly halved, regulatory T cells doubled, and Dr. Cox's immune age decreased by two years. This immune rejuvenation lowers long-term disease risks and highlights how targeted diet and lifestyle choices can rapidly reset immune aging.