Do Herbal Supplements for Men Actually Work? The Evidence (2026)

By Jordan Harvey · 1 July 2026 · Updated 7 July 2026 · 13 min read

“Do herbal supplements for men actually work?” is a fair question and a frustrating one to answer briefly — because the honest answer is “some do, in specific situations, with specific evidence; some do not.” The category averages out to mediocre because most products are sold without standardisation, at sub-clinical doses, with marketing that overstates what the trials support. The few ingredients that are genuinely evidence-backed look very different on closer inspection from the ones that ride that label without earning it.

This UK evidence review walks through seven of the most commonly sold herbal ingredients in men’s health products, grades them against the same standard (regulatory approval and human RCT data), and identifies which ones deliver real benefit, which ones come close, and which ones do not. The aim is the opposite of an “everything works” product page: just the data, with the funding sources, sample sizes, and limitations on the table. For deeper dives on individual ingredients, see the linked Shilajit, Tongkat Ali, and Korean Ginseng guides.

How We Rated the Evidence

Three grades, applied consistently across all seven ingredients:

• Strong evidence: regulatory-approved health claim (EFSA), or multiple high-quality RCTs replicated by independent groups, or a Cochrane review with at least moderate certainty.
• Moderate evidence: at least one rigorous placebo-controlled RCT plus supportive secondary data (meta-analysis with caveats, secondary trials), with the limitation that sample sizes are small or studies are manufacturer-funded.
• Weak / insufficient evidence: only animal data, in vitro mechanism without human RCTs, or human studies with serious methodological problems.

1. Zinc — The Only Ingredient with a Regulatory-Approved Testosterone Claim Strong Evidence

Zinc is unique on this list. It holds an EFSA-approved health claim (ID 301): “Zinc contributes to the maintenance of normal testosterone levels in the blood.” It also has approved claims for fertility and reproduction (ID 297/300) and for normal immune function. No other ingredient sold for men’s testosterone in the UK can legally make this claim (EFSA Journal, 2010).

The clinical evidence behind that approval: in a study of 9 zinc-deficient elderly men (mean age 64), six months of supplementation nearly doubled serum testosterone from 8.3 to 16.0 nmol/L (p=0.02) (Prasad et al., Nutrition, 1996). The effect is concentrated in men with deficiency or marginal status — in zinc-sufficient men, supplementation does not push levels higher. The benefit, in other words, is preventing deficiency-driven decline rather than enhancing already-healthy levels.

2. Tongkat Ali — Promising Testosterone Data, Growing Evidence Base Moderate Evidence

Tongkat Ali (Eurycoma longifolia) has the strongest emerging testosterone data after zinc. A 2022 meta-analysis of 5 RCTs covering 232 participants found a statistically significant increase in total testosterone (SMD 1.352, 95% CI 0.565–2.138, p=0.001), with the effect strongest in hypogonadal men (SMD 1.861, p=0.002) (Leisegang et al., Medicina, 2022). A 6-month double-blind RCT in men with age-related androgen decline found 200mg/day alongside exercise improved both erectile function and total testosterone versus placebo (Leitão et al., 2021).

The honest limitation: the meta-analysis covers 232 participants, modest by pharmaceutical standards. The pooled studies were largely manufacturer-funded (Biotropics Malaysia’s Physta extract), although the meta-analysis itself is academically independent. The convergence of industry and independent results is what earns the moderate-evidence rating.

3. Korean Ginseng — The Largest Evidence Base for Erectile Function Moderate Evidence

Korean Ginseng has been studied more than any other herb on this list for men’s sexual health. A 2021 Cochrane-style review of 9 RCTs (587 men) found the ability to achieve intercourse improved 2.55× vs placebo (RR 2.55, 95% CI 1.76–3.69), with moderate-certainty evidence (Lee et al., 2021). A larger 2025 meta-analysis of 14 RCTs (1,227 men) found significant improvements in erectile function (SMD 0.41), sexual desire (SMD 0.45), and even serum testosterone (SMD 0.23) (Ho et al., 2025).

4. Shilajit — Striking Results, but Independence Questions Moderate Evidence

Shilajit’s headline RCT is a 90-day, double-blind, placebo-controlled trial in 75 men aged 45–55: 250mg purified shilajit twice daily was associated with a 20.45% rise in total testosterone and 19.14% in free testosterone versus placebo (Pandit et al., Andrologia, 2016). The trial was funded by Natreon, the manufacturer of PrimaVie shilajit. The same group’s earlier open-label trial in oligospermic men showed a 23.5% testosterone increase (Biswas 2010). To date, no independent group has replicated the testosterone findings. The 2024 systematic review of 15 clinical studies (1,254 participants) found no serious adverse events — safety is solid; replication of the testosterone result is the open question.

5. Maca Root — Desire Without Testosterone Change Moderate Evidence

Maca (Lepidium meyenii) is unusual: a double-blind RCT found that 1,500mg and 3,000mg daily improved sexual desire from week 8, but without any change in serum testosterone or oestradiol (Gonzales et al., 2002). The mechanism appears to be central-nervous-system mediated. A 2010 systematic review of 4 RCTs concluded “limited evidence” (Shin 2010). A 2023 meta-analysis found a modest positive effect on erectile function in men with mild ED (MD 1.13, p=0.01).

6. L-Arginine — The Blood Flow Precursor Moderate Evidence

L-Arginine is the direct precursor to nitric oxide, the molecule that triggers blood vessel relaxation. The mechanism is uncontested; the question is whether the dose used in supplements matches the dose used in the trials. A multicentre double-blind RCT found 6g/day for 3 months significantly improved erectile function scores, with 74% of men showing improvement (Menafra et al., 2022). An earlier RCT using 5g/day found 31% improvement on L-arginine vs 12% on placebo (Chen 1999). For details on the wider blood-flow pathway, see our nitric oxide supplements guide for men.

7. Horny Goat Weed — The Ingredient That Does Not Have Human Evidence Weak Evidence

Horny goat weed (Epimedium) is one of the most commonly added ingredients to men’s health supplements and one of the least supported by human data. Its lead compound, icariin, is a mild PDE5 inhibitor in vitro — but its activity is roughly 1/80 of sildenafil, and there are no published human RCTs of erectile function with rigorous design. The handful of small clinical studies have used proprietary blends, not standardised icariin extract. As a single ingredient, the human evidence base does not support a confident effect claim.

Funding & Independence: A Quick Audit

A short transparency table for the headline studies:

How Herbal Supplements Compare to Prescription ED Treatments

The most honest comparison in this whole space is between the herbal evidence base and the sildenafil evidence base. Sildenafil’s 27-RCT meta-analysis (n=6,659) found 57% successful intercourse on sildenafil vs 21% on placebo — an effect size that no herbal ingredient on this list comes close to (JAMA Internal Medicine, 2002). For acute, on-demand erectile reliability, prescription PDE5 inhibitors are the evidence-led answer. For wider context on the herbal-vs-prescription decision, see our Horny Goat Weed review and the wider Tongkat Ali guide.

What the herbal literature points to is a different proposition: a daily upstream routine spanning hormonal, blood-flow and energy pathways, taken daily over weeks and months. That is not a sildenafil substitute — it is a different problem being solved. Many men over 40 use both, sequenced sensibly: a daily multi-ingredient formula for the foundation, and PDE5 inhibitors on demand when extra reliability matters.

Forms, Doses & Standardisation: What Separates Real Products from Marketing

Across all seven ingredients, four quality criteria separate evidence-aligned products from marketing-only products:

Are Herbal Supplements Safe?

Across the seven ingredients in this guide, the safety picture at clinical doses is generally reassuring, but the risks worth flagging are real:

How to Choose Quality Herbal Supplements in the UK

Five practical filters that account for almost all of the difference between trial-grade and marketing-grade products:

• Standardisation on the label. Eurycomanone %, ginsenoside %, fulvic acid %, icariin %. No percentage = no comparison to the trial.
• Dose match to the published RCT. Tongkat Ali 200mg, Shilajit 500mg, Korean Ginseng 1,000–3,000mg root equivalent, L-Arginine 5–6g.
• Third-party Certificate of Analysis. Heavy metals, microbial contamination, pharmaceutical adulterants.
• UK or EU GMP certification. The floor, not the ceiling.
• No proprietary blends. The per-ingredient mg should be on the label.

Why Does Blue Power Use the Evidence-Backed Ingredients?

Frequently Asked Questions About Herbal Supplements for Men

The Bottom Line: Do Herbal Supplements Work for Men?

Of seven of the most-sold herbal ingredients in UK men’s health products, one has regulatory approval (zinc), four have meaningful human RCT data with caveats (Tongkat Ali, Korean Ginseng, Shilajit, L-Arginine), one has unusual evidence for desire without hormonal change (maca), and one essentially does not have rigorous human evidence as a single ingredient (horny goat weed). The honest answer to “do herbal supplements work?” depends entirely on which supplement, in which dose, with which standardisation, in which population.

The structural problem with the category is not that the good ingredients do not work — the meta-analyses, Cochrane reviews, and EFSA claims show several of them do, in the contexts they were studied. The problem is that most products on the shelf are not the products that were studied. Solving that is a quality problem, not a science problem — standardisation on the label, dose match to the trial, third-party CoA, no proprietary blends.

For UK men weighing the question for themselves, the most efficient approach is a short, transparent stack of the ingredients with the strongest evidence (zinc, Tongkat Ali, Shilajit, Korean Ginseng, L-Arginine), at clinical-style doses with verified standardisation, taken daily for at least 8–12 weeks before judging the effect. Skip the long marketing lists and the proprietary blends. The category gets better one product at a time when the buyer asks for the things that actually separate trial-grade from marketing-grade.