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Herbs for Men’s Health

By Heather Davis, MS, RDN, LDN

Despite the increasing interest and use of herbal medicines for a variety of conditions and concerns, there remains a considerable research gap. Many unanswered questions exist regarding herbal metabolism, dose-dependent impact, and long-term effects. In addition, many studies looking at the medicinal properties of herbal bioactive compounds have been conducted in vitro and can’t offer as much conclusive insight into how these compounds behave in a more complicated metabolic setting in vivo. Nonetheless, some promising in vivo herbal studies exist that fan the fire of curiosity and spur investigation.

Some herbs are marketed for men’s health, including prostate health, hormone balance, and fertility. About 30% to 50% of infertility is related to male infertility and although reproductive diseases, lifestyle choices, and environmental (including nutritional) factors are among the main causes, researchers are asking how certain herbs might improve outcomes and if they have a valid place in the clinical arsenal for improving fertility in men.1

Mechanism of Impact
Experts offer several explanations for how some herbs may influence male fertility, including improving antioxidant status and reducing oxidative stress in sperm cells, increasing the number of testicular vessels, increasing the lifespan of sperm, and increasing sperm quality. It’s also possible that some herbs may enhance the activity of the hypothalamic-pituitary-gonadal axis, affecting the secretion of LH and testosterone.2

High levels of reactive oxygen species (ROS) are directly linked to infertility, damaging sperm cell membrane lipids. Elevated ROS may also harm sperm motility by impairing sperm mitochondrial function and decreasing spermatogenesis by way of negatively impacting the hypothalamic-pituitary-gonadal axis.2 This is why the potential therapeutic action of some fertility-supportive herbs may be attributed to their suspected antioxidant action, including the way they may influence the cell signaling processes that regulate endogenous antioxidant factors.

However, certain herbs and dosages may warrant caution, possibly increasing the risk for infertility by reducing gonadotropins and testosterone, reducing sperm count, motility, and sperm viability.2

Herbs of Interest
A 2016 systematic review published in The Iranian Journal of Obstetrics, Gynecology, and Infertility evaluated a variety of studies published from 2000 to 2015 on the topic of herbs and male fertility. They concluded that Petroselinum crispum (parsley), Allium sativum (garlic), Matricaria chemmomilla (German chamomile), Crocus sativus L. (saffron crocus), Origanum vulgarel L. spp. viride (a type of oregano), and Daucus carota L. (wild carrot) may have male fertility-enhancing properties. In contrast, they concluded that Curcurma Longa (turmeric), Piper nigrum (black pepper), Achillea millefolium L. (yarrow), Centella Asiatica (gotu kola), Tinospora cordifolia (guduchi or amrita), Martynia annua (cat’s claw), Anethum graveolens (dill), Barleria prionitis (porcupine flower), and Abrus precatorius (rosary pea) had male antifertility characteristics.3

Some potential limitations of this review include the inconsistent dosages used across different studies and the lack of higher quality human clinical data. It’s also unclear to what degree in vitro research was included and may have skewed results.3

The Brazilian Journal of Assisted Reproduction published a systematic review in 2022 to further explore the use of herbal medicine in male fertility, including evaluating the effects of herbal products on sperm and testosterone production. Assessing 35 papers published between 2000 to 2020, nine medicinal plants were found to affect the male reproductive system in beneficial ways. However, this review included predominantly animal studies as well as some in vitro findings. The limited human studies reviewed primarily focused on Withania somnifera (ashwagandha), which they found had a positive effect in the treatment of infertility both in males and females. It should be noted that some studies they reviewed diverged from these findings and suggested that Withania somnifera extract might have nonfertilizing and spermicidal effect. These contradictory findings underscore the importance of more rigorous human trials to determine safety parameters.1

Most recently, a 2024 meta-analysis was published in Pharmacological Research - Modern Chinese Medicine reviewing the impact of herbal medicines on human serum reproductive hormone levels, semen parameters, and antioxidant enzymes. Publications were excluded from the analysis if they were in vitro studies, animal studies, lacked data, or contained inaccurate data presented solely through graphs, conference abstracts, reviews, case series, or case reports. A total of 23 articles were involved in the final meta-analysis, including papers from China, Korea, Iran, Peru, Japan, Malaysia, and India published between 2001 and 2018. From this data, authors felt there was consistent evidence supporting the use of Mucuna pruriens (velvet bean or lacuna bean), Withania somnifera, and Eurycoma longifolia (longjack) to improve male fertility parameters.2

Mucuna pruriens may act through its dopaminergic, aphrodisiac, and antioxidant properties. Three studies reviewed in the meta-analysis found that participants receiving Mucuna pruriens at a dosage of 5 g/day for three months showed significant improvements in sperm parameters, hormonal levels, and antioxidant profiles compared with control groups in populations with different fertility statuses.2 

Withania somnifera may influence hormone regulation and antioxidant activity. Two randomized controlled trials comparing Withania somnifera with placebo- or pentoxifylline-treated groups, and one prospective cohort study comparing Withania somnifera with the control group, all produced similar results, demonstrating improvement in semen parameters and sex hormone levels. After 90 days of using Withania somnifera, serum testosterone and luteinizing hormone levels in oligospermic males significantly increased.2

Eurycoma longifolia contains small peptides known as “eurypeptides,” which have been shown to enhance energy status and sex drive in rodent studies. In human studies, four comparative and follow-up studies on healthy men, infertile individuals, and men with hypogonadism demonstrated positive outcomes in terms of both sex hormones and sperm quality. Findings suggest this herb may have potential to address male infertility by improving testosterone levels, sperm quality, and overall reproductive health.2

Concerning the limitations of the Chinese report, the authors say there was no long-term observation period to assess long-term effects and no way to examine the outcome of successful conception. Looking ahead, it will be crucial to conduct clinical trials with stricter criteria. These trials should compare the effectiveness of herbal medicines with that of commercially available drugs that are currently used to treat male infertility. They also point out that combinations of herbs may lead to better outcomes than individual herbs because of synergistic effects.2

Nutrition Foundations
With some encouraging research underway, it may be easy to jump to conclusions about the safety profiles of certain herbal treatments for male infertility. Although some herbs mentioned here may be safe and effective in certain cases at certain dosages, all authors heavily emphasize the need for more long-term experimental and clinical studies. In many cases, great variability exists in study results, likely owing to the nature of dose-dependent behavior in herbal bioactives.

Furthermore, before recommending or relying on herbal medicines to help treat male infertility, it may be prudent to ensure that an individual has a strong nutritional foundation in place. Herbal bioactive metabolism relies on many biochemical pathways that will, in turn, rely on nutrient substrates and cofactors for optimal function. In addition, studies of preconception diet suggest that nutrition plays a powerful role in supporting fertility.4 According to researchers, increasing fish and reducing sugary drinks, processed meats, and total fat may improve male fertility, while consuming adequate essential fatty acids, carbohydrates, and reducing processed meat can improve sperm health.4

There’s likely no single food, herbal supplement, or other magic pill that will by itself sufficiently address male infertility. Fertility researchers across the map point to the need for more studies looking at whole-diet and synergistic comprehensive approaches to treatment for best results.

— Heather Davis, MS, RDN, LDN, is editor of Today’s Dietitian.

References
1. Boroujeni SN, Malamiri FA, Bossaghzadeh F, Esmaeili A, Moudi E. The most important medicinal plants affecting sperm and testosterone production: a systematic review. JBRA Assist Reprod. 2022;26(3):522-530.

2. Nguyen-Thanh T, Dang-Ngoc P, Bui MH, Le-Minh T, Nguyen-Vu QC. Effectiveness of herbal medicines on male reproductive system: evidence from meta-analysis. Pharmacol Res - Mod Chin Med. 2024;12:100462.

3. Roozbeh N, Rostami S, Abdi F. A review on herbal medicine with fertility and infertility characteristics in males. IJOGI. 2016;19(13):18-32.

4. Tully CA, Alesi S, McPherson NO, et al. Assessing the influence of preconception diet on male fertility: a systematic scoping review. Hum Reprod Update. 2024;30(3):243-261.