Maca, Ginseng, Tongkat Ali and Horny Goat Weed: What the Research Says for Men
Pick up almost any men's vitality supplement and you will see the same four plants on the label: maca, panax ginseng, tongkat ali and horny goat weed. They are the backbone of the category, including blends like Peak State. Here is what the human research actually shows for each one, what it does not show, and why the dose on the label matters more than the name.
| Herb | Sold for | What human studies show | Typical researched dose | Verdict |
|---|---|---|---|---|
| Maca | Libido, drive | More self reported desire vs placebo, no testosterone change | 1500 to 3000 mg/day | Modest, real for desire |
| Panax ginseng | Erections, energy | Trivial effect on validated scores, low certainty | 1000 mg/day or more | Weak, inconsistent |
| Tongkat ali | Testosterone, stamina | Raises testosterone, mostly in deficient men; lowers stress markers | 200 to 400 mg/day | Best of the four for testosterone |
| Horny goat weed | Harder erections | Blood flow mechanism in the lab only, almost no human trials | Not established in men | Least human evidence |
Does maca work for men?
Short answer: for desire, yes, modestly. For firmness, the evidence is weak.
Sold for: libido and drive.
What the studies show: Maca has some of the better evidence in this group for one narrow thing, self reported sexual desire. In a 2002 controlled trial (PubMed 12472620), men who took maca for 12 weeks reported more desire than men on a placebo, and the effect showed up without any change in testosterone or estradiol. A small 2009 trial in 50 men with mild erectile difficulty (PubMed 19260845) found a modest edge for maca over placebo on erectile function scores. A systematic review in 2010 (PubMed 20691074) read all of this as promising but limited, with small studies and mixed methods.
Bottom line: The most reasonable expectation is a gentle lift in interest, not a change in firmness, and not in everyone. It is generally well tolerated.
Does panax ginseng help erections?
Short answer: the best review of the evidence says the effect is trivial, on low certainty data.
Sold for: erections and energy.
What the studies show: Ginseng is the most studied ingredient here, and the most carefully reviewed. A Cochrane systematic review in 2021 (PubMed 33871063) found that on validated questionnaires, ginseng had only trivial effects on erectile function or satisfaction compared with placebo, and the certainty of that evidence was low. The same review noted ginseng may improve a man's own sense of being able to have intercourse. Earlier pooled analyses of Korean red ginseng looked more positive, but those trials were smaller and weaker.
Bottom line: Real research interest, weak and inconsistent results, and the doses used in trials are usually 1000 mg or more per day, which a shared 800 mg blend cannot deliver on its own.
Does tongkat ali raise testosterone?
Short answer: yes, in clinical trials, with the biggest effect in men who were low to begin with.
Sold for: testosterone and stamina.
What the studies show: Tongkat ali has the clearest signal for testosterone. A 2022 meta analysis of clinical trials (PubMed 36013514) found it raised total testosterone, with the effect strongest in men who started out deficient. A 2013 trial in moderately stressed adults (PubMed 23705671) reported lower stress hormone readings and better mood scores. Direct evidence that it firms up erections is thin, and often comes from studies where it was paired with exercise.
Bottom line: The best supported use is supporting testosterone and stress resilience in tired or run down men, not a same night performance aid.
Does horny goat weed work?
Short answer: it has an interesting mechanism in the lab, but almost no evidence in real men.
Sold for: harder erections.
What the studies show: The active compound is icariin. In laboratory work (PubMed 18778098) it blocks the same enzyme that some prescription erection tablets act on, which is why it gets marketed the way it does. The catch is potency and proof. In those same lab studies plain icariin is many times weaker than the prescription drug it is compared with, and there are very few trials in actual men. Most of the positive data is in rodents.
Bottom line: A genuine mechanism on paper, almost no human evidence, and the amount inside a general blend is unlikely to reach a meaningful dose.
Horny goat weed also shows up in supplements sold under the viral blue salt trick name.
Why the dose matters more than the label
Every herb above has a range of doses used in research. Ginseng trials often run past 1000 mg a day. Maca trials use 1500 to 3000 mg. When a product hides everything inside one 800 mg proprietary blend, there is no way to know whether any single ingredient is near a researched dose or just a pinch for the label. That is the main thing to check before you spend money, and it is the main mark against most blends in this category.
Want a blend that includes these herbs? Testing the category once with a 60 day money back guarantee makes sense if you would rather not buy four separate tubs. Two we have reviewed dose by dose: the Peak State capsule (hides its doses in an 800 mg blend, sold in NZ, AU and CA) and the IronPulseX gummy (prints every dose, sold in the US, UK, NZ, CA and AU).
If firmness rather than drive is your main concern, it is worth understanding why erections get softer after 40 first, and working through what actually helps at home, because the everyday causes usually matter more than any capsule. The circulation side of these formulas, L-arginine and beetroot, is covered in the nitric oxide guide. And if a change in erections came on fast, that is a reason to see a doctor before trying any supplement.
Common questions
Does horny goat weed really work for erections?
Its active compound, icariin, blocks the same enzyme that some prescription erection tablets act on, but only in laboratory studies, where it is many times weaker. There are very few trials in men, and most of the positive results are in rodents. The amount inside a general blend is unlikely to reach a useful dose.
How much maca should a man take?
Trials that saw an effect on desire used 1500 to 3000 mg a day of dried maca, usually for at least eight weeks. A shared 800 mg proprietary blend that also has to fit four other herbs cannot deliver that on its own.
Is tongkat ali safe to take daily?
In studies it is generally well tolerated at 200 to 400 mg a day for up to six months. It can interact with medication for blood pressure, the heart and blood thinning, and with hormone sensitive conditions, so check with a doctor first if any of that applies.
Which of the four has the best evidence?
Maca for desire and tongkat ali for testosterone in run down men have the most consistent human data. Panax ginseng is the most studied but the results are weak and mixed. Horny goat weed has the least human evidence of the four.
References
Effect of Lepidium meyenii (Maca) on sexual desire and its absent relationship with
serum testosterone levels in adult healthy men. Andrologia, 2002.
PubMed 12472620
Subjective effects of Lepidium meyenii (Maca) extract on well-being and sexual
performances in patients with mild erectile dysfunction: a randomised, double-blind
clinical trial. Andrologia, 2009.
PubMed 19260845
Maca (L. meyenii) for improving sexual function: a systematic review.
BMC Complement Altern Med, 2010.
PubMed 20691074
Ginseng for erectile dysfunction. Cochrane Database of Systematic Reviews, 2021.
PubMed 33871063
Eurycoma longifolia (Jack) improves serum total testosterone in men: a systematic
review and meta-analysis of clinical trials. Medicina, 2022.
PubMed 36013514
Effect of Tongkat Ali on stress hormones and psychological mood state in moderately
stressed subjects. J Int Soc Sports Nutr, 2013.
PubMed 23705671
Potent inhibition of human phosphodiesterase-5 by icariin derivatives.
J Nat Prod, 2008.
PubMed 18778098
Medical note. This article is general information, not medical advice. Herbs can interact with medication. If you take anything for blood pressure, the heart or blood thinning, or you have a health condition, talk to your doctor before starting a supplement.
Affiliate disclosure. If you buy through links to Peak State on this site, we may earn a commission from the seller. You pay the same price, and it does not change what we write.