Yarnell E. Improving men's health with botanicals. Altern Complement Ther. June 2016;22(3):120-124.

Yarnell reviews some of the best-supported herbs to prevent and in some cases treat men's major health concerns.

Benign prostatic hyperplasia (BPH) is experienced by "all men, if they live long enough," and whether or not symptoms ever develop, saw palmetto (Serenoa repens, Arecaceae) fruit is inexpensive, easy to use, has a low risk of adverse effects, and may help prevent or delay BPH. While meta-analyses of studies of saw palmetto in symptomatic BPH suggest the herb is only minimally effective, in other trials it was as effective as the drug finasteride and worked synergistically with it to shrink the prostate. Trials specifically exploring its usefulness in young, symptom-free men are needed, but even in their absence, Yarnell recommends saw palmetto as a preventive measure for men beginning in their 30s and early 40s.

Pygeum (Prunus africana, Rosaceae) bark "produces no action different from" saw palmetto, but comes from an endangered African tree, whereas saw palmetto grows wild and abundantly in Florida in the United States. Yarnell discourages use of pygeum because of this sustainability issue, while suggesting that, if cultivated, pygeum could be sustainable for use in Eurasia and Africa.

Stinging nettle (Urtica dioica, Urticaceae), the second best-researched herb for use in BPH but less understood, appears to work in completely different ways. In combination with saw palmetto, stinging nettle relieved symptoms long term as effectively as finasteride. However, it should not be used by men with symptomatic BPH, as it is a diuretic and can worsen symptoms. While not studied for prevention, Yarnell finds it sensible to use stinging nettle for that purpose.

After BPH symptoms emerge, in addition to saw palmetto, stronger spasmolytic herbs may be called for, such as khella (Ammi visnaga, Apiaceae) fruit. However, if the prostate reaches a weight of > 50 g, either chemical 5α-reductase inhibitors, surgery, or even stronger spasmolytics may be needed.

Most botanical agents that can reduce the risk of prostate cancer, and specifically of aggressive prostate cancer, are actually foods. Pomegranate (Punica granatum, Lythraceae) fruit contains ellagitannins converted by the gut microbiota to major therapeutic compounds such as urolithin A, with numerous anticancer effects in the prostate gland. While it is not known whether pomegranate can prevent prostate cancer, it is a very safe treatment for men with low-grade cases. In a meta-analysis of epidemiological studies, higher intake of garlic (Allium sativum, Amaryllidaceae), and to some extent other Amaryllidaceae family members, significantly reduced risks of prostate cancer. Not all epidemiologic studies have reported a protective effect, but many studies have found that garlic destroys prostate cancer cells in vitro. Soy (Glycine max, Fabaceae), and to some extent other Fabaceae family members, contain isoflavones, protein, and the Bowman-Birk protease inhibitor that inhibit prostate cancer. Clinical trials, case-controlled studies, and epidemiological studies variously report that soy foods, especially tofu, and the isoflavones genistein and daidzein, lower risks of prostate cancer. While this evidence continues to mount, it does not account for individual legume response. Specific gut flora is needed to convert daidzein to S-equol and genistein to 5-hydroxy-S-equol in order for legumes to exert a protective effect, and these organisms are not available in any supplement or fermented food. People of Asian descent who eat traditional diets produce the most equol. Dairy products may encourage equol-forming bacteria and antibiotics may destroy them.

Coronary artery disease, metabolic syndrome, erectile dysfunction (ED), diabetes mellitus (diabetes type 2), and secondary hypogonadism are all common in men (and, except for ED, women) and are linked by underlying causes. Pomegranate fruit juice is antiatherosclerotic and in one randomized trial significantly helped men with mild-to-moderate ED after only two weeks compared with placebo. Garlic and soy might be similarly beneficial, although they are not yet studied in arteriogenic ED. In traditional Chinese medicine (TCM), horny goat weed (Epimedium brevicornum, Berberidaceae) leaves and related species are important for treating ED. In combination with other herbs, horny goat weed was effective in reducing mild-to-moderate ED in two clinical trials; other ingredients are not detailed here. Saffron (Crocus sativus, Iridaceae) has been found useful in ED in two open trials and one controlled trial that specifically studied antidepressant-induced ED. Another TCM herb even better documented for use in ED is Asian ginseng (Panax ginseng, Araliaceae) root, an adaptogen with stress-relieving and antiatherosclerotic effects. Yarnell points out that ginseng fruit, more sustainably harvested than roots, also appears to have benefits in ED.

A specific type of hypogonadism in obese men with metabolic syndrome, prediabetes, or diabetes includes high levels of estradiol. While little information is available on herbal treatments for this condition, phytoestrogens such as those in soy and other legumes may block the pituitary-suppressive effects of excess estradiol; studies are warranted.