Best Supplements for Men Over 40: Evidence-Based UK Guide (2026)

By Jordan Harvey · Published 27 April 2026 · Updated 22 July 2026 · 17 min read

After 40, something shifts. Energy dips. Recovery takes longer. The drive that once felt effortless starts requiring more effort. There is a biological reason: the Massachusetts Male Aging Study — one of the largest longitudinal studies ever conducted on male hormones — found that total testosterone declines at roughly 1.6% per year in men over 40, with bioavailable testosterone dropping even faster at 2–3% per year (Feldman et al., JCEM, 2002). By age 50, that is a meaningful decline. By 60, it is unmistakable.

But here is what most “best supplements for men” articles do not tell you: only two supplement health claims in the UK have been approved by EFSA (the European Food Safety Authority) with direct relevance to testosterone — both for zinc. This guide separates EFSA-approved claims from clinical-trial evidence for seven ingredients, each studied separately for testosterone, blood flow, energy, or stress resilience. For the full clinical evidence on Tongkat Ali or shilajit, see the dedicated ingredient guides. If you are closer to 50 than 40, our companion guide to the best supplements for men over 50 covers the age-specific differences.

Why Do Men Over 40 Need Different Supplements?

The supplement needs of a 25-year-old and a 45-year-old are fundamentally different. After 40, three biological shifts converge simultaneously. First, testosterone production declines as the hypothalamic-pituitary-gonadal (HPG) axis becomes less responsive — a 2024 review in Frontiers in Endocrinology confirmed that GnRH secretion, the hormone that triggers testosterone production, is predicted to decline 33–50% between ages 20 and 80 (PMC, 2024). Second, oxidative stress accumulates as mitochondrial efficiency drops, reducing cellular energy. Third, nutrient absorption decreases as stomach acid production falls — zinc deficiency prevalence rises to 19.7% by the eighth decade of life (Nature Scientific Reports, 2024).

This is not about taking a generic multivitamin. It is about targeting the specific pathways that decline after 40: zinc status, blood flow, cellular energy, and stress resilience. The eight supplements below each address one or more of these pathways, ranked here by strength of regulatory and clinical evidence.

Get Tested First: What UK Men Over 40 Should Check

After 40, guessing is expensive and slow. A blood test tells you what is actually happening — rather than what a marketing claim assumes is happening. Before spending money on any supplement, it is worth asking your GP for, or ordering privately from a UK-regulated lab, the following baseline checks.

Total and free testosterone. A morning blood draw (ideally before 11am, when testosterone is typically at its daily peak) gives the most reliable reading, because levels fall through the day. Total testosterone is commonly reported in nmol/L on a UK lab report, which will include the local reference range — ranges vary slightly between laboratories. A single low reading is usually repeated on a separate morning before a GP considers a diagnosis of low testosterone (hypogonadism).

Vitamin D (25-hydroxyvitamin D, or “25-OH-D”). This is the standard vitamin D blood test, reported in nmol/L in the UK. NHS guidance treats levels below 25 nmol/L as deficient, with levels above roughly 50 nmol/L generally considered adequate. See our full guide to vitamin D and testosterone in men for what the evidence does, and does not, show.

Ferritin (iron stores). Persistent tiredness, poor recovery, and low drive can all overlap with iron deficiency, which is easily missed if the assumed cause is “just testosterone.”

HbA1c (average blood glucose over roughly three months). Poorly controlled blood sugar is independently linked with lower testosterone and with vascular symptoms, so it is worth ruling out or managing alongside anything else.

None of this replaces a GP consultation. Supplements — including Blue Power — are designed to support a normal, varied diet; they are not diagnostic tools and cannot replace a blood test or a doctor’s assessment. If your results fall outside the normal range, that is a conversation for your GP, not a supplement aisle.

What Are the 8 Best Supplements for Men Over 40?

Quick Reference: Ageing Pathways, Ingredients & Food Sources

Before the ingredient-by-ingredient detail, here is how the four main pathways affected after 40 map to an ingredient, a dietary source, and further reading:

1. Zinc EFSA Approved

Zinc is the only mineral with an EFSA-approved health claim specifically linking it to testosterone. The authorised wording under EU Regulation 432/2012 is: “Zinc contributes to the maintenance of normal testosterone levels in the blood.” It also carries the authorised claim that “Zinc contributes to normal fertility and reproduction.” For men over 40, this makes zinc the single most important mineral supplement — and the one with the strongest regulatory backing in the UK.

The problem: zinc status declines with age. A 2024 analysis in Nature Scientific Reports found that zinc deficiency prevalence rises steadily after 40, reaching 19.7% by the eighth decade. If your testosterone is declining and your zinc is low, supplementation addresses both the symptom and a potential nutritional root cause (EFSA, 2010). For the full picture on this pathway, see our guides to zinc and testosterone and the best vitamin supplements for men.

Study Funding Transparency

Understanding who funded the key clinical studies cited in this guide helps weigh the evidence correctly:

2. Vitamin D NHS Recommended

The NHS recommends that all UK adults take 10 micrograms (400 IU) of vitamin D daily during autumn and winter (October–March), because sunlight exposure is insufficient to maintain adequate levels at UK latitudes. For men over 40, this is especially critical: a UK Biobank analysis found that 22–34% of UK men have vitamin D levels below the deficiency threshold of 25 nmol/L, and men are 7% more likely to be deficient than women (PMC, 2021; NHS.uk).

Beyond bone health, vitamin D acts as a steroid hormone precursor. Multiple observational studies have found correlations between low vitamin D and low testosterone — though direct causality in intervention trials remains debated. What is not debated: if you are a UK man over 40, you almost certainly need to supplement vitamin D at least six months of the year. EFSA has approved claims for vitamin D’s contribution to normal immune function, bone health, and muscle function. See our full guide to vitamin D and testosterone in men for the underlying evidence and its limits.

3. Tongkat Ali Strongest Evidence

Tongkat Ali is not an ingredient in Blue Power. It is reviewed here for context, because it is one of the most widely marketed men's-health herbs in the UK, and Blue Power uses Oat extract (Avena sativa) in its place. Tongkat Ali (Eurycoma longifolia) has something most herbal supplements lack: a meta-analysis. The 2022 Leisegang meta-analysis pooled 5 randomised controlled trials and found a statistically significant increase in total testosterone (SMD 1.352, 95% CI 0.565–2.138, p=0.001) across both healthy and hypogonadal men (Leisegang et al., Medicina, 2022).

A 2021 RCT in 105 men aged 50–70 with low testosterone found that 200mg/day of standardised Tongkat Ali extract was associated with statistically significant rises in testosterone at weeks 4, 8, and 12 (p<0.001), alongside improvements in muscle strength (Chinnappan et al., 2021). Note: this trial finding cannot be transferred as a label claim to Blue Power; Blue Power contains Oat extract (Avena sativa) 10:1 50mg per tablet, compared with the 200mg dose used in this trial. A 2024 study in already-trained athletes found no effect — which is informative: across these trials, the changes in testosterone were observed mainly in men with low or suppressed baseline levels rather than in men with already-healthy levels. These are trial findings and cannot be transferred to Blue Power as label claims.

4. Shilajit Strong Evidence

Shilajit is a mineral-rich resin from Himalayan rock formations. In a double-blind, placebo-controlled RCT of 75 healthy volunteers aged 45–55, purified shilajit at 250mg twice daily for 90 days was associated with a 20.45% change in total testosterone, a 19.14% change in free testosterone, and a 31.35% change in DHEA-S versus placebo (Pandit et al., Andrologia, 2016). This trial finding cannot be transferred as a label claim to Blue Power; Blue Power contains Shilajit 50mg per tablet, compared with 500mg/day used in this trial.

Shilajit’s mechanism is distinct from Tongkat Ali: it works primarily through fulvic acid, which improves mitochondrial function and enhances the transport of minerals (including zinc) into cells. The limitation: we currently have 1–2 well-designed human RCTs, so the evidence base is promising but narrower than that for zinc or Tongkat Ali.

5. Maca Root Strong Evidence

Maca (Lepidium meyenii) has been studied in randomised controlled trials in men. The Gonzales 2002 RCT (n=57) found that 1,500–3,000mg/day was associated with greater self-reported sexual desire scores from week 8 onward, while serum testosterone and oestradiol levels were unchanged versus placebo — suggesting a central nervous system or neuroendocrine mechanism rather than an HPG axis effect (Gonzales et al., Andrologia, 2002). These trial findings cannot be transferred to Blue Power as label claims.

A 2023 RCT in men with late-onset hypogonadism symptoms found that 1,000mg/day of maca for 12 weeks was associated with improved IIEF scores (+3.2 points) and a reduction in ADAM symptom prevalence from 73% to 51% (Shin et al., World J Mens Health, 2023). These trial findings cannot be transferred to Blue Power as label claims; Blue Power contains Maca 50 mg vs the 1,000 mg/day used in this trial. Maca has not been shown to raise testosterone levels. For more on how maca is used and sourced, see our guides to maca root benefits and maca powder vs maca root.

6. Korean Ginseng Moderate Evidence

Korean Ginseng (Panax ginseng) is one of the most-studied adaptogens. A 5:1 extract delivers active ginsenosides at therapeutic concentrations. A 2021 Cochrane review assessed ginseng for erectile dysfunction and found a modest but consistent association with improved IIEF-15 scores (MD 3.52, low-to-moderate certainty) (Lee et al., Cochrane, 2021). This trial finding cannot be transferred to Blue Power as a label claim; Blue Power contains Korean Ginseng 5:1 100 mg.

Ginseng is primarily studied as an adaptogen: it modulates cortisol and supports energy in fatigued or stressed men. The Cochrane evidence is low-to-moderate certainty, and independent replication would strengthen the findings. Read more in our dedicated Korean Ginseng benefits guide.

7. L-Arginine Strong Evidence

L-Arginine is the direct precursor to nitric oxide (NO) — the molecule that dilates blood vessels and enables blood flow. For men over 40, declining NO production is one of the main reasons vascular function changes with age. A 2019 meta-analysis of 10 RCTs involving 540 patients found that L-Arginine supplementation (1,500–5,000mg/day) was associated with improved erectile-function scores versus placebo (OR 3.37, 95% CI 1.29–8.77, p=0.01) (Rhim et al., J Sex Med, 2019). This trial finding cannot be transferred to Blue Power as a label claim; Blue Power contains L-Arginine 50 mg vs the 1,500–5,000 mg/day used in these trials.

The mechanism is direct: L-Arginine → nitric oxide synthase → NO → vasodilation → improved blood flow. This pathway is relevant to cardiovascular health broadly, not just one outcome. For the full evidence on this pathway, see our guides to L-Arginine and blood flow and nitric oxide supplements for men.

8. Vitamin C EFSA Approved

Vitamin C carries the EFSA-authorised claim that “Vitamin C contributes to the reduction of tiredness and fatigue” — one of the most common complaints men over 40 raise with their GP. It is supplied at 80mg, 100% of the daily reference intake, in each tablet.

Vitamin C is not glamorous, but it is a genuine essential nutrient the body cannot make. The only claim stated for it here is the authorised wording above; no other benefit is asserted.

Forms, Standards & How to Read a Men’s Supplement Label

Every ingredient in this guide exists in multiple commercial forms — and form matters. A “Tongkat Ali extract” without eurycomanone standardisation is not equivalent to the extracts used in clinical trials. Here is what to verify before buying:

How Much Should Men Over 40 Take? Clinical Dosage Guide

The doses listed in the TL;DR above are what clinical trials actually used in standalone studies. In a multi-ingredient formula, individual doses are lower — this is not a deficiency, it is the nature of including multiple ingredients within a single tablet. What matters is full transparency: you should always know exactly how much of each ingredient you are getting.

Timelines also matter. In the Chinnappan 2021 RCT, Tongkat Ali showed statistically significant testosterone-related outcomes from week 4 onward, building through 12 weeks. Shilajit required 90 days in Pandit 2016. Maca showed improvements in self-reported sexual desire scores from week 8 in Gonzales 2002. As a general rule, allow 8–12 weeks before judging effectiveness — changes do not happen overnight.

Are There Any Side Effects or Safety Concerns?

At doses used in clinical trials and found in responsible multi-ingredient formulas, the ingredients reviewed in this guide have good safety profiles. Zinc at 10mg (100% NRV) is well within safe upper limits (EU Tolerable Upper Intake Level: 25mg/day for adults). Vitamin C at 80mg is extremely well tolerated. Tongkat Ali at 200–400mg/day showed no serious adverse events in trials lasting up to 9 months. Shilajit at 500mg/day reported no liver, kidney, or haematological abnormalities in the Pandit 2016 RCT.

The exceptions worth flagging: taking zinc chronically above 50mg/day can impair copper absorption. Tongkat Ali has an unresolved EFSA novel food status issue (genotoxicity was observed at 2,000mg/kg in rats — the human equivalent of roughly 140,000mg, far above clinical doses). Raw, unpurified shilajit may contain heavy metals; always use purified shilajit with a Certificate of Analysis.

How to Choose Quality Men’s Supplements in the UK

The men’s supplement market is flooded with products exploiting insecurity with bad science. Before buying anything, verify these five criteria:

• Full ingredient transparency: Every ingredient listed individually with its dose in milligrams. Avoid any product using “proprietary blend” without disclosing individual amounts. You should be able to compare each ingredient dose against the clinical trials cited.
• Standardised herbal extracts: Tongkat Ali should specify eurycomanone %; shilajit should specify fulvic acid %; ginseng should specify ginsenoside %. Extract ratio labels without bioactive content percentages are meaningless for comparing to clinical evidence.
• Third-party testing with Certificate of Analysis: An independent laboratory CoA confirms ingredient identity, active compound content, absence of heavy metals, and microbial safety. UK MHRA-registered manufacturers are legally required to maintain these records.
• GMP certification: UK or EU Good Manufacturing Practice. Without GMP, there is no quality assurance over the production process — your “500mg of shilajit” could be anything.
• No illegal health claims: In the UK, supplements cannot legally claim to treat, cure, or prevent any disease. These are medicinal claims reserved for licensed medicines. Any product making disease-treatment claims for a food supplement is violating MHRA regulations and should be avoided entirely — a food supplement is not a treatment; consult your GP if you have a medical concern.

The Foundations: What Beats Any Supplement After 40

No ingredient in this guide, at any dose, outperforms the basics. Four factors move the needle more than any tablet — and they cost nothing.

Sleep. Testosterone release is concentrated in the earlier part of the sleep cycle. Chronic short sleep (routinely under 5–6 hours a night) has been associated with meaningfully lower testosterone in controlled studies — a decline comparable in size to roughly 10–15 years of ageing. If sleep is poor, that is worth fixing before anything else.

Resistance training. Regular resistance exercise is one of the most consistently reproduced lifestyle factors linked to healthy testosterone and body composition in men over 40, alongside broader cardiovascular and metabolic benefits. It does not need to be extreme: two to three sessions a week of compound lifts (squats, presses, rows) is enough to matter.

Waist size and body fat. Excess fat carried around the waist increases the conversion of testosterone into oestrogen via the enzyme aromatase, and is one of the more modifiable drivers of low testosterone in overweight men. A waist circumference above roughly 94cm (37in) is generally used as a marker of increased metabolic risk in UK men — worth discussing with a GP if you are above this.

Alcohol. Regular heavy drinking suppresses testosterone production directly and disrupts the deep sleep needed for hormone release. Staying within the UK Chief Medical Officers’ guideline of 14 units a week, spread across three or more days, is a reasonable, evidence-aligned target.

This is not a moral lecture — it is a cost-benefit one. Sleep, training, waist size, and alcohol intake are larger, better-evidenced levers than any single supplement ingredient in this guide. Supplements are additive to these basics, not a substitute for them. For a broader age-by-age view, see our men’s health supplement guide by age.

Why Does Blue Power Include 7 Ingredients in One Daily Tablet?

Two of the nutrients above carry authorised EU nutrient claims. These apply to the individual nutrient at its reference intake, not to the formula as a whole: Zinc contributes to the maintenance of normal testosterone levels in the blood. Vitamin C contributes to the reduction of tiredness and fatigue.

For men who want to include oat extract (Avena sativa), shilajit, and zinc, plus four further evidence-reviewed ingredients, in their daily routine, Blue Power removes the research burden and the cost of sourcing multiple separate supplements. The individual doses are lower than standalone clinical trials — this trade-off (breadth across multiple ingredients vs depth in one) is fully disclosed, because transparency is the point.

Retail prices vary; figures are indicative of single-ingredient UK high-street pricing.

Frequently Asked Questions About Supplements for Men Over 40

The Bottom Line: Are Supplements Worth It for Men Over 40?

The testosterone decline after 40 is documented, longitudinal, and clinically meaningful — 1.6%/year from the Massachusetts Male Aging Study data. The question is not whether it happens, but whether targeted supplementation can support the specific pathways affected. The evidence says yes, for the right ingredients at appropriate doses.

The hierarchy matters. Zinc has EFSA regulatory approval — the highest bar in the UK. Tongkat Ali has a meta-analysis of 5 RCTs. Shilajit has one strong RCT with a striking 20% testosterone result. Vitamin D has explicit NHS guidance. The others have multiple human trials showing consistent effects on their target outcomes. No supplement replaces sleep, exercise, and a decent diet — but for UK men over 40 who are already doing the basics, the clinical evidence for these seven ingredients is real, published, and verifiable.

Quality matters above all else. Standardised extracts with verified bioactive percentages. Full dose transparency. GMP certification. Third-party testing. Without these basics, you cannot compare a product to its clinical evidence base — and you should not spend money on it.