Big Blasts May Set Veterans' Aging Clocks Running Fast

The hardest explosion a combat veteran ever felt may leave a mark in the blood. Among 114 combat veterans who served after 9/11, those who reported the most intense blast pressure showed signs that their cells were aging faster.

The study was cross-sectional, using veterans from two Veterans Affairs research studies in the Southeast. Their average age was 43, and nearly 89 percent were men.

Researchers measured biological aging with DunedinPACE, a blood test that reads chemical tags on DNA to estimate how quickly a body is aging. Each veteran was also interviewed about every blast they could recall, from training to combat, rating features like the pressure wave, flying debris and ground shaking. The key measure was the worst pressure rating on a zero-to-five scale, where five meant extreme pressure linked to injury.

Greater blast severity tracked with a faster aging pace, and the link held after PTSD and mild brain injury were factored in. Mild brain injury showed its own link. PTSD did not.

Veterans whose worst blast rated a four or five averaged faster than the group, while those at three or below averaged slower. Only 18 veterans reached those top tiers, and the authors suggest the effect may appear only after high-level blasts.

How a pressure wave could leave its mark on those DNA tags is an open question. The authors point to inflammation, oxidative damage and blood vessel problems as possible routes. The study design cannot prove cause, and blood draws and interviews came an average of six years apart. Most participants hadn't reached the ages when age-related disease usually appears.

Nobody in the study was aging backward, even those who scored below average. Those who felt the biggest blasts just seemed to be on a faster clock.

Read the full story at Journal of Head Trauma Rehabilitation, March 18, 2026

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