Best Fertility Supplements for Men: Evidence-Based Guide (2026)

By Blue Power Research Team  ·  10 June 2026  ·  10 min read

Male factor is involved in approximately 50% of all infertility cases — solely responsible for around 20% and contributing to another 30–40% (StatPearls, Male Infertility). In the UK, roughly 1 in 7 couples experience fertility difficulties (NICE CG156). Globally, the WHO reports that 1 in 6 people of reproductive age will experience infertility in their lifetime (WHO, 2025).

The encouraging news? Several supplements have real clinical evidence for improving sperm parameters — count, motility, morphology, and DNA integrity. This guide ranks the best fertility supplements for men based on the quality and strength of the evidence, from meta-analyses and RCTs down to observational data.

What Supplements Help Male Fertility? The Evidence-Based List

1. Zinc EFSA Approved

Zinc is the only mineral with an EFSA-approved health claim stating it “contributes to normal fertility and reproduction” (EU Regulation 432/2012, Claim IDs 297, 300). It also carries a separate authorised EFSA claim, worded verbatim as “Zinc contributes to the maintenance of normal testosterone levels in the blood.” (Claim ID 301). This isn’t marketing — it’s regulatory science.

A 2016 meta-analysis of 20 studies confirmed that infertile men have significantly lower seminal zinc than fertile controls, and that zinc supplementation significantly increases semen volume, sperm motility, and the percentage of normal morphology (Zhao et al., Sci Rep, 2016).

Zinc is essential for spermatogenesis (the 74-day process of sperm production), sperm membrane stabilisation, and testosterone metabolism (Fallah et al., 2018). The UK Reference Nutrient Intake (RNI) for men is 9.5mg/day, but studies showing fertility benefits typically used 15–50mg/day.

2. CoQ10 (Coenzyme Q10) Strong Evidence

A 2025 meta-analysis of 8 RCTs involving 877 men (462 CoQ10, 415 controls) found statistically significant improvements in total sperm count (P<0.0001), total motility (P<0.00001), progressive motility (P=0.0006), normal morphology (P=0.004), and testosterone (P<0.00001) (Akhigbe et al., 2025).

CoQ10 is concentrated in the mitochondrial midpiece of sperm, where it functions as both an energy-producing agent and an antioxidant. This dual role directly supports sperm motility — the single most important parameter for natural conception. Most studies used 200mg/day for 3–6 months. A systematic review also found CoQ10 supplementation significantly improved clinical pregnancy odds (OR: 6.02) (Alahmar et al., 2021).

3. Selenium

A double-blind RCT of 69 subfertile men found that 3 months of selenium supplementation significantly improved sperm motility (P=0.023), with 56% of men showing a positive response and 11% achieving paternity during the study — compared to 0% in the placebo group (Scott et al., 1998).

Selenium’s importance for male fertility centres on selenoprotein GPx4 (glutathione peroxidase 4) — a critical structural protein in the sperm midpiece. Without adequate selenium, sperm cannot maintain structural integrity during maturation. Approximately 30% of oligoasthenospermic men show dramatically decreased GPx4 levels (GPx4 review, 2019). A larger study of 690 infertile men given selenium (200μg) combined with vitamin E (400IU) for 14 weeks found that 52.6% showed improvement in motility or morphology, with a 10.8% spontaneous pregnancy rate (Moslemi & Tavanbakhsh, 2011).

4. Vitamin C Antioxidant

Ascorbic acid contributes approximately 65% of total seminal antioxidant activity — making it the single most important antioxidant in semen. A study of 13 infertile men given 1,000mg vitamin C twice daily for 2 months showed remarkable improvements: sperm count increased from 14.3 to 32.8 million/mL, motility from 31.2% to 60.1%, and normal morphology from 43% to 66.7% (all P<0.001) (Akmal et al., 2006).

A network meta-analysis comparing multiple antioxidant supplements ranked vitamin C as the best antioxidant for improving sperm morphology across all supplements tested. This is significant because morphology — the shape and structure of sperm — is one of the harder parameters to improve with supplementation.

5. L-Carnitine

L-carnitine is naturally abundant in the epididymis, where it supports fatty acid transport into sperm mitochondria for energy production. A systematic review of 8 RCTs found that L-carnitine supplementation improved total motility by +10.72% (mean difference), progressive motility by +9.82%, and morphology by +2.41% (Mongioi et al., 2022). A separate double-blind RCT also found significant decreases in sperm DNA fragmentation and improved clinical pregnancy and live birth rates (Gamal et al., 2023).

6. Omega-3 Fatty Acids (DHA/EPA)

DHA constitutes approximately 60% of total polyunsaturated fatty acids in spermatozoa and is critical for sperm membrane fluidity, capacitation, and the acrosome reaction (the chemical process that allows sperm to penetrate the egg). A meta-analysis of 3 RCTs involving 290 men found that omega-3 supplementation significantly increased sperm motility (RR 5.82, P<0.0001) and seminal DHA concentration (Hosseini et al., 2019).

7. Vitamin D

A systematic review of 23 observational and 10 interventional studies found the strongest correlation between vitamin D and sperm motility — with 16 of 23 studies showing a positive association. Six of 10 intervention studies showed improved progressive motility with vitamin D supplementation (De Angelis et al., 2023).

This is particularly relevant for UK men: vitamin D deficiency is highly prevalent due to limited sunlight. Public Health England recommends 10μg (400 IU) daily for all adults during autumn and winter. Many fertility practitioners suggest 1,000–2,000 IU daily for men trying to conceive.

Honourable Mention: Shilajit for Male Fertility

A clinical trial of 35 oligospermic men (28 completers) given 200mg/day processed shilajit for 90 days found striking improvements across every parameter: sperm count +61.4%, spermia +37.6%, motility +12.4–17.4%, normal sperm +18.9%, and serum testosterone +23.5% (P<0.001). Semen MDA (an oxidative stress marker) decreased by 18.7%. Liver and kidney function remained normal throughout (Biswas et al., Andrologia, 2010).

Limitation: this was a single study without a placebo control and a small sample size. It needs replication in a larger, blinded RCT. But the magnitude of the changes — particularly the 61.4% sperm count increase — warrants attention.

Summary: Fertility Supplements Compared

How Long Do Fertility Supplements Take to Work?

Spermatogenesis — the full cycle of sperm production — takes approximately 74 days. This means any supplement you start today won’t affect the sperm being produced for at least 2.5 months. Most fertility studies measure outcomes at 3–6 months, and that’s the realistic timeframe for expecting measurable improvements.

Frequently Asked Questions

The Bottom Line

Male fertility supplements aren’t snake oil — there’s genuine clinical evidence that zinc, CoQ10, selenium, vitamin C, and omega-3s can improve measurable sperm parameters. The key is choosing supplements backed by meta-analyses and RCTs rather than marketing claims, taking them consistently for at least 3 months, and starting with a baseline semen analysis so you can track real progress.

For men who want a daily foundation that includes zinc (EFSA fertility claim), vitamin C (the primary seminal antioxidant), and shilajit (mineral transport and antioxidant support), Blue Power provides these alongside five other evidence-backed men’s health compounds in a single tablet. For a broader guide to supplementation for men in midlife, see our guide to the best supplements for men over 40.