Which supplements have randomized controlled trials showing increased semen volume in men over 50?

1. Market claims versus the evidence: marketing leans on small trials

Manufacturers and PR outlets repeatedly tout clinical trials to support volume‑boost claims. For example, Semenax is described across multiple releases and promotional articles as having double‑blind, placebo‑controlled data reporting a roughly 20–30% increase in ejaculate volume compared with placebo in trials of adult men (trial sizes reported around 63–78 participants, ages cited as 30–60 or “adult men”) ^{[2] [3] [1]}. These are company‑linked reports and syndicated press pieces, not independent peer‑reviewed meta‑analyses—so the evidence base is small and heavily tied to vendors ^{[1] [2]}.

2. Age specificity: the over‑50 question is largely unanswered in available items

The sources frequently note semen volume declines with age and target older men in marketing, but they do not provide clear RCTs conducted exclusively in men older than 50. Semenax trials mentioned included men aged roughly 30–60, which overlaps with but does not isolate an over‑50 cohort; other products cite mixed adult samples or ingredient‑level studies without age‑specific RCTs for the 50+ group ^{[2] [3] [1]}. Available sources do not mention any RCTs limited to men over 50.

3. Ingredient‑level evidence vs. finished product RCTs

Some articles point to ingredient research—zinc supplementation and its association with semen parameters is referenced repeatedly, and reviews claim zinc may increase semen volume and other sperm measures ^[4]. But the coverage mixes observational correlations, ingredient trials, and vendor trials of proprietary blends; it does not provide robust, independent RCTs proving a finished supplement raises ejaculate volume specifically for men >50 ^[4].

4. Quality and independence concerns: many sources are marketing or PR

Several items in the dataset are press releases, brand‑linked newswire pieces, or commercial reviews (Semenax press releases, Semenoll/GN releases, affiliate review sites) that amplify product trial claims ^{[1] [5] [6]}. These materials often highlight positive percentage changes but lack independent peer review, detailed methods, or subgroup analyses by age—raising a risk of bias and limited generalizability to older men ^{[1] [2]}.

5. What clinicians and journalists say about safety and realism

Health reporting in mainstream outlets warns consumers that “load‑boosting” supplements are heavily marketed and that experts urge caution on safety and effectiveness; a Men’s Health piece contextualizes how aging affects semen volume and suggests skepticism about hyperbolic promises ^[7]. That piece underscores that clinicians view many commercial claims skeptically and that physiological causes of reduced volume in older men are multifactorial ^[7].

6. Bottom line for someone over 50 seeking evidence‑based options

If you are specifically asking which supplements have RCTs showing increased semen volume in men over 50, current reporting in these sources does not identify any RCTs restricted to that age group—most clinical claims involve mixed adult samples or small vendor‑sponsored trials and are publicized via marketing channels rather than independent journals ^{[2] [3] [1]}. Ingredient studies (e.g., zinc) show associations with semen parameters, but available sources do not establish conclusive RCT evidence for finished products in the 50+ population ^[4].

If you want next steps based on these sources: consult a urologist (as Men’s Health recommends) about measurable causes of low semen volume; critically evaluate any product’s study details (sample age range, trial size, peer‑review status); and treat vendor press releases as preliminary rather than definitive evidence ^{[7] [1] [2]}.