Best Supplements for Libido: Evidence-Based Options for Men and Women (2026)

What is the best supplement to increase libido?

For most people, the best first step is checking for zinc and vitamin D deficiency — both directly impair testosterone synthesis and are common. If foundational levels are adequate: maca root (1.5–3g/day) has the most consistent RCT evidence for improving libido in both men and women without affecting hormone levels directly. Ashwagandha (KSM-66, 300–600 mg/day) is best when stress is a driver — it addresses cortisol-mediated testosterone suppression. Tongkat ali is well-studied for men with low-normal testosterone (especially as free testosterone). For women specifically: maca and ashwagandha have both shown meaningful improvements in female sexual function scores in RCTs. There is no single "best" supplement — the right choice depends on the underlying cause.

Do testosterone supplements actually work?

The term "testosterone booster" is marketing language that covers very different mechanisms. Supplements that have genuine RCT evidence for raising testosterone: shilajit (~23% increase in one 90-day study in men 45-55), ashwagandha (14-17% increase in multiple studies), zinc (restores testosterone suppressed by deficiency), vitamin D (raises testosterone in deficient men). Supplements that help "free" testosterone by reducing SHBG: tongkat ali, boron, zinc. Supplements with indirect mechanisms (libido without raising testosterone): maca root, fenugreek. Testosterone supplements are appropriate for men in the low-normal range — they are not the same as testosterone replacement therapy (TRT) and will not produce TRT-level effects. If you have clinically low testosterone (confirmed by blood test), consult an endocrinologist about TRT rather than relying on supplements.

What are the best libido supplements for women?

Female libido is more complex and contextual than male libido, influenced significantly by relationship quality, mental health, hormone balance (estrogen, progesterone, testosterone, cortisol), and medication side effects (particularly SSRIs and oral contraceptives). The most evidence-backed options for women: (1) Maca root — the best-studied botanical for female sexual dysfunction; RCTs show improvements in arousal, orgasm, and satisfaction, including specifically for SSRI-induced sexual dysfunction. (2) Ashwagandha (KSM-66) — a 2019 RCT showed significant improvements across all female sexual function domains. (3) Magnesium + vitamin D + zinc — address common deficiencies that affect hormone balance and energy (libido requires physical energy). For SSRI-related sexual dysfunction specifically: maca is the strongest supplement option alongside medical consultation about medication adjustment. DIM (diindolylmethane) may help women with estrogen dominance-related low libido.

Is maca root safe and effective for libido?

Yes — maca has an excellent safety profile and is one of the most consistently effective libido supplements across multiple RCTs. It is a root vegetable from the Andes and is consumed as a food staple in Peru. Side effects are rare; some people experience GI discomfort at high doses. Crucially: maca works for libido through mechanisms that do NOT involve sex hormone changes — it does not raise estrogen or testosterone. This is good news for women concerned about hormone-sensitive conditions (breast cancer risk, PCOS) and people on hormonal medications. The 2010 systematic review of 4 RCTs concluded maca improves subjective experience of sexual dysfunction with a convincing dose-response and good tolerability. Practical dose: 1.5–3g/day of maca extract (or 3–5g of raw maca powder), for 8–12 weeks to see full benefits.

How long does it take for libido supplements to work?

Timeline varies by supplement. Fastest effects: l-arginine for blood flow (1–2 hours when taken acutely as needed); maca may show mood and energy effects within 2 weeks. Medium timelines (4–8 weeks): ashwagandha for cortisol and stress-related libido; tongkat ali for SHBG and free testosterone. Longer timelines (8–12 weeks): shilajit and most testosterone-supporting supplements show maximum effects at 12 weeks. Vitamin D takes 8–12 weeks to raise blood levels meaningfully from supplementation. Zinc correction of deficiency: 4–8 weeks. The pattern: hormonal changes take weeks-to-months because they require sustained changes in signaling pathways, not acute pharmacological effects. Set expectations at 8–12 weeks of consistent daily use before evaluating effectiveness.

Can low libido be a sign of low testosterone?

Yes — low testosterone (both in men and women) is one of the most common hormonal causes of reduced libido. In men: testosterone declines approximately 1% per year after age 30; clinically low testosterone (hypogonadism) is defined as total testosterone below 300 ng/dL with symptoms including low libido, fatigue, and reduced motivation. In women: testosterone is present at about 1/10th the male level and is equally important for libido; low testosterone in women (often from oral contraceptive use, oophorectomy, or natural decline) significantly reduces sexual desire. Other signs of low testosterone beyond libido: fatigue, reduced motivation and drive, loss of muscle mass, mood changes, brain fog, reduced morning erections (men). Getting a morning testosterone blood panel (total + free testosterone + SHBG + LH + FSH) provides actionable data before choosing which supplements to target.