Groundbreaking research reveals how sperm changes as you become older — and why it matters for the next generation.
What if your age doesn’t only influence whether you can father a child, but also what genetic information you pass on?
A new Nature study sheds light on how sperm evolve over time — and the hidden implications for male fertility and offspring health.
New Findings: Sperm Accumulate Mutations Over Time
In the landmark study “Sperm sequencing reveals extensive positive selection in the male germline” (Nature, 2025), scientists analysed sperm from men aged 24 to 75 using high-precision whole-genome sequencing (NanoSeq).
Their results were striking:
- Sperm acquire about 1.67 new mutations per year per haploid genome.
- Some mutations undergo positive selection, meaning certain altered cell lines multiply and persist.
- Over 40 genes involved in development or cancer were affected.
Info-Box:
A haploid genome is the complete set of genetic information found in a single sperm or egg cell.
Unlike most body cells, which carry two copies of each chromosome (one from the mother and one from the father), sperm and egg cells have only one copy — that’s what “haploid” means.When a sperm and an egg join at fertilisation, their two haploid genomes combine to form a diploid genome — a full set of paired chromosomes for the new individual.
Most importantly:
The authors report that positive selection during spermatogenesis drives a two- to three-fold increased risk of known disease-causing mutations, resulting in 3–5% of sperm from middle-aged and older men carrying a pathogenic mutation.
These findings reveal previously underappreciated germline selection dynamics — and highlight that the risk of disease in children born to older fathers is broader than once believed.
Why This Matters
While most sperm mutations remain harmless, the accumulation — and selective propagation — of pathogenic variants with age underscores why sperm quality matters as much as quantity.
This doesn’t mean that fatherhood at a later age is unsafe. Rather, it emphasises the importance of supporting sperm health and DNA integrity through lifestyle and targeted nutrition.
Supporting Sperm Health from the Inside Out
We cannot change natural genetic processes, but we can strengthen the biological environment in which sperm develop.
Micronutrients and antioxidants are key for maintaining sperm metabolism, reducing oxidative stress, and supporting DNA repair:
- Zinc and selenium — contribute to normal spermatogenesis and protect cells from oxidative damage.
- Coenzyme Q10 and carnitine — are involved in energy production in sperm.
- Antioxidants — help neutralise free radicals that can damage sperm DNA.
Together, these nutrients help protect sperm cells from external stressors that encourage mutational events — supporting healthy conception and long-term offspring well-being.
Lifestyle Matters
In addition to micronutrient support, everyday habits make a measurable difference:
- Avoid smoking and excessive alcohol consumption.
- Maintain a healthy weight and balanced diet.
- Engage in regular physical activity.
- Reduce exposure to heat, toxins, and chronic stress.
Such steps can further reduce oxidative stress and support sperm DNA stability — no matter your age.
Conclusion
The new Nature study reshapes how we think about male reproductive ageing.
It’s not just about sperm count or motility — but about genetic integrity.
For men over 35 — or those planning for fatherhood later in life — supporting sperm health through optimal micronutrient and antioxidant intake (e.g. with Fertilovit®) is a proactive step towards protecting not only fertility, but also the health of their future child.
Frequently Asked Questions (FAQ)
Can supplements prevent genetic mutations in sperm?
No — mutations occur naturally as part of cell division.
However, antioxidants and micronutrients can reduce oxidative stress, one of the main causes of DNA damage, and therefore lower the risk of new mutations arising.
At what age does the risk of sperm mutations increase?
The Nature study found a linear increase in mutations with age, starting from early adulthood.
From around 35 years onwards, clear differences in sperm DNA integrity become noticeable.
Can sperm mutations affect a baby’s health?
In some cases, yes. Certain mutations have been associated with a slightly higher risk of developmental or genetic conditions.
That said, individual risk remains low — and maintaining good overall health and optimal micronutrient levels can help minimise potential effects.
Why is Fertilovit® particularly valuable for older men?
Because it provides the key micronutrients and antioxidants required for energy production, protection, and DNA repair — including zinc, selenium, CoQ10, vitamin C, and vitamin E.
Together, these nutrients support sperm metabolism and help maintain DNA integrity — crucial for healthy conception.
Which lifestyle habits also improve sperm quality?
Regular physical activity, a nutrient-dense diet, maintaining a healthy weight, avoiding smoking, and managing stress all have proven benefits for sperm health.
When combined with a tailored supplement such as Fertilovit® , these habits create the best possible foundation for strong, genetically healthy sperm.
In summary:
Ageing is inevitable — but supporting your body’s natural defences isn’t.
The right nutrients, combined with healthy lifestyle choices, can help safeguard sperm DNA and protect the health of your future child.
References
Aitken RJ, De Iuliis GN. On the possible origins of DNA damage in human spermatozoa. Mol Hum Reprod. 2010 Jan;16(1):3-13. doi: 10.1093/molehr/gap059. Epub 2009 Jul 31. PMID: 19648152.
Scientific Opinion on the substantiation of health claims related to zinc and selenium and normal spermatogenesis. EFSA Journal 2009; 7(9):1229
Neville MDC, Lawson ARJ, Sanghvi R, Abascal F, Pham MH, Cagan A, Nicola PA, Bayzetinova T, Baez-Ortega A, Roberts K, Lensing SV, Widaa S, Alcantara RE, García MP, Wadge S, Stratton MR, Campbell PJ, Small K, Martincorena I, Hurles ME, Rahbari R. Sperm sequencing reveals extensive positive selection in the male germline. Nature. 2025 Oct 8. doi: 10.1038/s41586-025-09448-3. Epub ahead of print. PMID: 41062690.
