Testosterone Cypionate and Accelerated Male-Pattern Hair Loss: Supplements With the Best Evidence

Does testosterone cypionate cause male-pattern hair loss?

The Depo-Testosterone label lists male pattern of baldness among the skin and appendage reactions that have occurred with some androgens, alongside hirsutism, seborrhea and acne, and gives no frequency [1]. The label's pharmacology section states that in many tissues the activity of testosterone appears to depend on reduction to dihydrotestosterone (DHT) [1].

Androgenetic alopecia, the medical name for pattern hair loss, is the most common form of hair loss, affecting up to 80% of men over a lifetime [8]. It develops through a progressive reduction in hair diameter, length and pigmentation, driven by DHT acting on androgen-sensitive follicles [8]. A 2019 review puts the conversion of testosterone to DHT at up to 10% of the body's testosterone [9]. A review of testosterone therapy in transgender men lists alopecia among the undesired effects and notes that it continues to develop after the first year [10].

Which supplements have evidence, and how strong is it?

The saw palmetto and ketoconazole studies involved men or patients with pattern hair loss. The biotin and zinc findings come from other conditions and do not show that either supplement treats male-pattern hair loss [4][5][6][7].

Saw palmetto

A randomized, double-blind, placebo-controlled pilot study of a liposterolic extract of saw palmetto (Serenoa repens) with beta-sitosterol enrolled men aged 23 to 64 with mild to moderate androgenetic alopecia. Blinded investigators rated 60% of the men given the active formulation (6 of 10) as improved at the final visit [4]. The authors described a highly positive pilot response and said it justified larger trials [4].

Biotin

A systematic review found 18 reported cases of biotin use for hair or nail changes. Every case involved an underlying pathology for poor growth, and all improved with supplementation; the authors concluded there is a lack of sufficient evidence for biotin supplementation in healthy individuals [6].

Zinc

The zinc evidence comes from a different condition. In a 12-week study of 15 people with alopecia areata and low serum zinc, oral zinc gluconate raised mean serum zinc from 56.9 to 84.5 mcg/dL, and 9 of 15 (66.7%) had a positive response, which was not statistically significant [7]. Alopecia areata is not androgenetic alopecia.

Other hair-loss options

Ketoconazole 2% shampoo

A controlled study compared ketoconazole 2% shampoo with an unmedicated shampoo, each used with or without 2% minoxidil, in people with androgenic alopecia. Hair density, hair size and the proportion of anagen follicles improved almost similarly with the ketoconazole and minoxidil regimens, and sebum levels fell with ketoconazole [5]. The authors concluded that ketoconazole may act on the course of the condition but that the clinical significance needed a larger controlled study [5].

Finasteride and minoxidil: the treatments with real trial data

Neither is a supplement, and both have far larger trials than anything above.

Finasteride 1 mg. In two 1-year trials, 1,553 men aged 18 to 41 with male-pattern hair loss took finasteride 1 mg daily or placebo, and 1,215 continued into blinded second-year extensions. Hair count in a 5.1 cm2 circle on the balding vertex rose by 107 hairs more than placebo at 1 year and 138 more at 2 years (P<0.001), while placebo-treated men lost hair progressively [2].

Topical minoxidil 5%. A 48-week trial randomized 393 men to 5% minoxidil (157), 2% minoxidil (158) or placebo (78), applied twice daily. The 5% solution was superior to both on non-vellus hair count and on patient and investigator ratings, producing 45% more hair regrowth than the 2% solution at week 48; itching and local irritation were more frequent with 5% [3].

A 2017 systematic review and meta-analysis found minoxidil, finasteride and low-level laser therapy all superior to placebo for hair growth in men with androgenetic alopecia, and noted that minoxidil and finasteride are the FDA-approved drug treatments for it [11].