Do ED and Erection Supplements Work? Research on Arginine, Citrulline, Maca, and More

Search for the “best supplement for erections” and you will see arginine, citrulline, maca, zinc, ginseng, vitamin D, and more.

These ingredients do not all have research of the same strength.

As of 2026, guidelines and systematic reviews show multiple clinical trials of L-arginine and ginseng for ED. L-citrulline and maca are supported mainly by small studies. Zinc, magnesium, vitamin D, and multivitamins need to be considered separately as ways to correct a deficiency and as supposed treatments for ED.

L-arginine has relatively more research

L-arginine is an amino acid involved in the pathway that produces nitric oxide.

Studies have combined several randomized controlled trials and reported improvement in some measures among men with mild to moderate ED.

A 2024 network meta-analysis of nutritional supplements examined 15 randomized controlled trials involving 1,000 men with ED. It found data suggesting improvement with L-arginine alone and when combined with an ED medicine.

The EAU ED guideline weakly recommends daily L-arginine or ginseng for men with mild ED who do not want drug treatment, provided they understand that the improvement may be small.

“Weak recommendation” is not the same position as a PDE5 inhibitor.

L-arginine is discussed in more detail in “Does L-Arginine Help ED and Erections?”

L-citrulline is supported mainly by small studies

L-citrulline is converted into L-arginine in the body.

A small study of 24 men with mild ED found that more participants improved their erection-hardness score. Another small study examined adding citrulline and similar ingredients for men using a PDE5 inhibitor.

There are still fewer trials than for L-arginine.

The EAU guideline does not give L-citrulline the same recommendation wording as L-arginine.

It is sometimes described as being more efficiently used by the body than arginine, but that does not show that it works better for ED.

Ginseng has research, but the benefit may be small

Panax ginseng has also been studied in multiple randomized controlled trials for ED.

A Cochrane systematic review included nine studies involving 587 men with mild to moderate ED. Ginseng improved the IIEF erectile-function score, but the authors judged that the clinical effect may be small and rated the certainty of evidence as low.

The EAU gives it, like L-arginine, a weak recommendation for men with mild ED who do not want drug treatment.

The evidence does not show that a naturally derived ingredient has the same treatment effect as a medical ED medicine.

Separate libido from erection hardness when considering maca

Maca is often marketed as a “sexual vitality” supplement.

A 2010 systematic review found four randomized controlled trials and reported some improvement in libido or sexual function. The number of trials, participant count, and study quality were insufficient for a firm conclusion.

A 2025 meta-analysis of herbal supplements also described the evidence for maca as insufficient.

A change in sexual desire is not the same as a change in erection hardness.

BananaUp’s supplement_maca is a record of days when someone used maca, not a recommendation to take it.

Separate low vitamin D from proof that supplementation improves ED

Observational studies have found more ED among men with low vitamin D.

An association is not the same as evidence that adding vitamin D improves ED.

The 2024 D-Health Trial examined three years of vitamin D supplementation and ED in 8,920 men. ED was reported in 58.8% of the vitamin D group and 59.0% of the placebo group, with no improvement effect confirmed.

Because a large randomized trial found no difference, the evidence is weak for adding vitamin D “for erections” in otherwise healthy men.

Replacing medically confirmed vitamin D deficiency is a separate issue from using a supplement as an ED treatment.

Do not extend deficiency findings to men who are not deficient in zinc

Zinc is often linked in online explanations to testosterone and sexual function.

Some older small studies found improvement in special populations such as dialysis patients with low zinc. Other studies have not found a clear sexual-function effect.

Correcting zinc deficiency is not the same as taking extra zinc when intake is already adequate and expecting stronger erections.

BananaUp’s supplement_zinc is available as an intake record, not as a promise of ED improvement.

Magnesium and multivitamins are not ED treatments in BananaUp

Magnesium is needed for many body functions, including muscles and nerves. Multivitamins can be used to fill nutritional gaps.

There is not enough clinical data to say that magnesium makes erections firmer or that a multivitamin treats ED.

Keep nutritional management for a deficiency separate from treatment effects on ED.

BananaUp’s supplement_magnesium and supplement_multivitamin are also records of intake days.

Be more cautious with the product category “men’s supplement”

Evidence for an ingredient is not evidence that a commercial combination supplement has the same effect.

A 2023 study evaluated commercially available ED supplements by their ingredients and the amount of research behind them. Eighty percent of the products were classified as having no promising efficacy under the study’s criteria. Many products with multiple ingredients also did not contain amounts that had been studied.

A 2020 systematic review likewise found that many ingredients in popular men’s supplements had contradictory, negative, or insufficient evidence.

The words “for men” or “sexual vitality” on a package are not clinical evidence.

Products marketed as “natural” can contain undeclared drugs

Products marketed for sexual enhancement continue to produce cases in which undeclared pharmaceutical ingredients are detected.

On September 15, 2026, the U.S. FDA warned that an unapproved sexual-enhancement product contained an undeclared tadalafil-like ingredient. In 2026, several other products were also reported to contain sildenafil or tadalafil without listing them on the label.

These ingredients can interact with nitrates and cause a dangerous drop in blood pressure.

“Natural” does not automatically mean safer than a medicine.

BananaUp does not rank supplements

BananaUp’s Supplement Log does not prescribe supplements or rank ingredients by saying which one is best.

It lets a person record an existing supplement and place the intake date next to their Condition.

Putting L-arginine, L-citrulline, maca, zinc, magnesium, vitamin D, and multivitamins in one list does not mean that the medical evidence for them is equally strong.

If you take medication, have a medical condition, or combine several supplements, check with a doctor or pharmacist. If difficulty getting or maintaining an erection continues for several weeks, seek medical advice before adding more supplements.

Use the Male Condition Check to organize daily context. In 14-day tracking, keep Supplement Log intake and daily physical Condition as separate fields.