Male Fertility: Lifestyle Changes and Supplements, What the research Says

What do male fertility supplements claim?

Products such as Wellman Conception and Proxeed, and single nutrients like CoQ10, zinc and selenium, are sold to "support sperm health". The idea is that sperm are vulnerable to oxidative stress (damage from unstable molecules), so antioxidants and key minerals should help sperm count, movement and DNA, and so the chance of pregnancy.

There is a real basis for this. Zinc and selenium are needed for normal sperm production, and men with poor diets can be short of them. The question is whether supplements help men who are not deficient.

What does the evidence show?

The Cochrane review

The 2022 Cochrane review pooled 90 studies of more than 10,000 men. It found very low-certainty evidence from 12 small or medium trials that antioxidants may improve live birth rates for couples at fertility clinics. But the authors concluded the evidence is "inconclusive" because of serious risk of bias and poor reporting. Antioxidants may cause mild stomach upset.

The large trials

Two well-run US trials are more sobering. In the MOXI trial, a daily antioxidant mix (including vitamins C, E, selenium, zinc and folate) did not improve sperm count, movement or DNA damage, and live births were not higher than with placebo. The much larger FAZST trial gave 2,370 men zinc and folic acid or placebo: no improvement in semen quality or live births.

What lifestyle changes help male fertility?

• Stop smoking. The NHS says smoking, including passive smoking, can reduce semen quality.
• Keep alcohol within 14 units a week, spread over three or more days. Heavy drinking can lower sperm quality.
• Lose excess weight. A BMI of 30 or more is linked to reduced fertility.
• Keep things cool. The NHS notes a link between scrotal heat and lower semen quality, though it is unclear whether loose underwear fixes it. Studies show laptops on the lap raise scrotal temperature, and men who mostly wore boxers had higher sperm concentrations than men in tight underwear. Limit hot baths, saunas and long periods with a laptop on your lap.
• Check medicines and supplements. Anabolic steroids and testosterone (including TRT and some online "boosters") can switch off sperm production.
• Avoid workplace chemicals where possible: the NHS lists some pesticides, solvents and metals.
• Get STIs checked, as chlamydia can affect fertility.

Sperm take about three months to develop, so changes take that long to show. That also means a short-term lapse, such as a heavy weekend or a fever, can affect a sperm test a few weeks or months later. If a semen analysis comes back low after an illness, your GP may suggest repeating it.

Diet matters too, though the evidence for any single food is weak. A varied diet with fruit, vegetables, wholegrains, fish, nuts and pulses provides the zinc, selenium and folate sperm production relies on, without the risk of overdoing it that comes with stacking supplements.

Who might reasonably try a supplement?

Men with a poor diet (little meat, fish, eggs, dairy, nuts or wholegrains) might reasonably take a modest zinc or selenium supplement to cover a gap. Couples already in fertility treatment sometimes try CoQ10 or an antioxidant mix on the basis of the Cochrane signal, ideally after discussing it with their clinic.

Who should be careful?

• Selenium: the NHS says to keep total intake at 350 micrograms a day or less. Too much can lead to hair and nail loss. Watch for selenium in multivitamins and Brazil nuts.
• Zinc: do not take more than 25mg a day from supplements unless a doctor advises it. Long-term high doses can lower copper.
• CoQ10: can interact with warfarin and may lower blood pressure. Ask a pharmacist if you take regular medicines.
• Doubling up: fertility multivitamins plus single nutrients can easily exceed limits.

If you want to try one: what to look for

We chose simple, unflavoured single-nutrient capsules so you know exactly what you are taking. We did not list multi-ingredient formulas: Wellman Conception, for example, lists maltodextrin alongside 30 or so nutrients and botanicals, which falls outside our policy on highly processed products, and blends make it harder to stay within limits.

Our picks at a glance

How we chose

Unflavoured, single-ingredient food supplements from a UK brand, with doses inside NHS limits, and no sweeteners, flavourings or maltodextrin. Viridian does not state batch-level third-party testing, which is a limitation.

Viridian Co-Q10 & MCT 100mg

100mg of CoQ10 (ubiquinone) in MCT oil, £33.25 for 30. CoQ10 is one of the antioxidants used in trials in the Cochrane review. Caveat: the best evidence for a better chance of a baby is very low certainty.

Viridian Zinc Citrate 15mg

15mg zinc for £8.80, a sensible top-up if your diet is low in meat, shellfish and dairy. Caveat: the FAZST trial found no benefit in men eating normal diets.

Viridian Selenium 200ug

200 micrograms of selenium for £8.70. Caveat: that is well above daily needs, and combined with food it can approach the NHS ceiling; most men do not need it.

When should you see a GP?

See your GP if you and your partner have been trying for a year without success, or sooner if your partner is 36 or over, you have had testicular problems, surgery or cancer treatment, or you notice a lump, pain or swelling in the testicles. Under NICE guidance, men are usually offered a semen analysis, with a repeat if the first is abnormal, and both partners are assessed together. A home sperm test can be a useful first look, but it does not replace this.

Bottom line

The best-supported steps are free: stop smoking, drink less, lose excess weight and keep the testes cool. Supplements are a small, uncertain extra, with large trials showing no benefit from antioxidant mixes or zinc with folic acid. If you have been trying for a year, see your GP for a semen analysis rather than relying on pills.