Telomere Length: What It Is, What Affects It, and Whether You Can Change It

Telomeres are repetitive DNA sequences that cap the ends of chromosomes, protecting them from deterioration during cell replication. With each cell division, a small portion of the telomere is lost. When telomeres reach a critical minimum length, the cell enters senescence or apoptosis. Shorter average telomere length is associated with increased risk of cardiovascular disease, dementia, type 2 diabetes, and all-cause mortality.

What Accelerates Telomere Shortening

• Oxidative stress: reactive oxygen species directly damage telomeric DNA and accelerate attrition
• Chronic psychological stress: elevated cortisol and catecholamines increase oxidative stress at telomeres. The telomeres of chronically stressed caregivers are significantly shorter than those of controls
• Smoking: one of the most potent accelerators of telomere shortening, with each pack-year associated with measurable additional attrition
• Obesity: particularly visceral adiposity, which produces oxidative stress and inflammatory cytokines that accelerate telomere loss
• Poor sleep: chronic sleep restriction accelerates telomere attrition through increased oxidative stress and inflammatory signalling

What Protects and Potentially Restores Telomere Length

• Exercise: the most consistently evidenced lifestyle factor for preserving telomere length. A 2017 BYU study found that adults exercising vigorously five days per week had telomere length equivalent to adults nine years younger
• Mediterranean diet: dietary patterns high in omega-3, polyphenols, and fibre are associated with longer telomeres
• Stress management: mindfulness-based interventions show preliminary evidence for slowing or reversing telomere attrition
• Telomerase activators: including TA-65, a cycloastragenol extract, with preliminary human evidence for telomere length preservation