Can Omega-3, Vitamin D and Exercise Slow Biological Age? A New Nature Aging Study Explores the Possibility
For years, scientists have known that exercise, good nutrition, and key nutrients each independently support long-term health. A 2025 study published in Nature Aging asked a more specific question: what happens when omega-3, vitamin D, and exercise are combined, and can we actually measure the effect at the cellular level?
What Is Biological Age?
Your chronological age is how many birthdays you've had. Your biological age reflects how well your cells and tissues are actually functioning, measured through DNA methylation "clocks", tools like PhenoAge, GrimAge, and DunedinPACE that estimate how fast your body is aging at a molecular level.
What Did Researchers Find?
This was a post hoc analysis of 777 participants from the DO-HEALTH trial, a randomized controlled trial testing vitamin D (2,000 IU/day), omega-3 (1g/day), and a simple home exercise program, alone and in combination, over three years.
Omega-3 alone showed a measurable protective effect, slowing three of the four aging clocks tested (PhenoAge, GrimAge2, and DunedinPACE). Exercise and vitamin D alone did not show the same independent effect. However, when all three, omega-3, vitamin D, and exercise, were combined, there was an additive protective effect specifically on the PhenoAge clock. Overall effects across the three years were modest, equivalent to roughly 3 to 4 months of slowed biological aging.
Why This Matters
This is one of the more rigorous studies in this space, a large randomized trial rather than a small pilot or observational study, using validated aging biomarkers rather than self-reported outcomes. It suggests omega-3 specifically deserves more attention in longevity conversations than it typically gets, and that combining simple interventions may offer a modest additive benefit beyond what any one alone provides.
What This Means for Everyday Life
This isn't evidence that exercise alone reverses aging, that claim isn't what the study found. It's evidence that a combination of accessible, low-risk habits, in this case daily omega-3, vitamin D, and light home exercise, may modestly slow biological aging over years, with omega-3 appearing to carry more of that effect than expected.
WithinOz Perspective
There's no single intervention here that "reverses aging," and it's worth being precise about that, even omega-3's effect was modest, a few months over three years. What this reinforces is something longevity science keeps circling back to: small, consistent habits, sustained for years, add up to measurable biological effects, even when no single piece looks dramatic on its own.
Study Details
Journal: Nature Aging
Study: Individual and additive effects of vitamin D, omega-3 and exercise on DNA methylation clocks of biological aging in older adults from the DO-HEALTH trial
Published: February 2025
Sample: 777 participants, DO-HEALTH trial
Key Finding: Omega-3 alone slowed 3 of 4 aging clocks; all three interventions combined showed additive benefit on PhenoAge specifically. Effects ranged from 2.9–3.8 months over 3 years.
Read the Original Research
Nature Aging: https://www.nature.com/articles/s43587-024-00793-y
Full text (PMC): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11922767/
DO-HEALTH trial overview: https://do-health.eu/individual-and-additive-effects-of-vit-d-omega-3-and-exercise-on-dna-methylation-clocks-of-biological-aging/
