DNA Methylation Shifts in Astronauts Reveal Reversible Biological Aging During Spaceflight

Spaceflight may not just accelerate aging—it could be a stress test for the body’s biological resilience, with DNA methylation changes rebounding faster than expected in astronauts.

Four astronauts on the nine-day Axiom-2 mission exhibited rapid DNA methylation changes during spaceflight, with epigenetic age shifts partially reversing post-landing.

Researchers used 32 epigenetic clocks—including chronological-age predictors, mortality-linked models, and immune-focused clocks—to measure biological age. Younger astronauts showed epigenetic ages below pre-flight levels within 24 hours of landing, suggesting biological elasticity.

Immune cell dynamics, particularly regulatory T cells and naïve CD4 T cells, accounted for much of the in-flight epigenetic acceleration. David Furman said:

"The findings suggest that spaceflight induces rapid, yet reversible, epigenetic changes that are partially distinct from cell shifts. This positions spaceflight as a platform to study aging mechanisms and test geroprotective interventions."

The study’s limitations include a small sample size (four astronauts), potential confounding factors like diet and sleep, and the inability to prove causality. Researchers propose spaceflight as a 'human aging model' by compressing stressors into a measurable window.

⚠️ LEGAL DISCLAIMER: It is for informational purposes only. It never substitutes for professional medical advice, diagnosis, or treatment. Always consult your doctor regarding any questions about your health.