What supplements can help increase testosterone levels and libido in a male patient?

Supplements for Testosterone and Libido: Evidence-Based Recommendations

There are no clear, reliable data to support the use of the variety of supplements (vitamins, antioxidants, nutritional supplement formulations) marketed for testosterone enhancement, and major clinical guidelines explicitly state this lack of evidence. 1

The Evidence Gap

The 2021 AUA/ASRM guidelines on male infertility directly address this question and conclude that supplements lack sufficient supporting data 1. This is further reinforced by research showing:

• 90% of "testosterone booster" supplements claim to boost testosterone, but only 24.8% have any published data supporting these claims 2
• 10.1% of supplement ingredients actually have data suggesting they decrease testosterone levels 2
• 61.5% of supplement ingredients have no published data whatsoever regarding their effect on testosterone 2
• Many supplements contain supra-therapeutic doses of vitamins and minerals, with 13 products exceeding FDA upper tolerable limits for zinc, vitamin B3, and magnesium 2

Limited Evidence for Select Agents

A 2022 scoping review identified only a handful of supplements with modest supporting evidence, and critically, these effects are modest and do not directly translate into clinical benefits 3:

Supplements with Some Supporting Data (in men with documented deficiency):

• Zinc - only in cases of zinc deficiency 3
• Vitamin D - only in cases of hypovitaminosis D 3
• L-arginine - limited evidence for both testosterone and sperm parameters 3
• Ashwagandha - based on small trials in men with low testosterone 3
• Mucuna - minimal evidence 3

Critical Limitations:

• These agents show effects only in men with documented deficiencies or low testosterone at baseline 3
• The magnitude of testosterone increase is small and clinically insignificant 3
• Androgen receptor content, not endogenous androgen levels, is the principal factor in muscle hypertrophy, meaning even if testosterone increases slightly, it may not produce desired physical effects 3

What Actually Works: Prescription Testosterone Therapy

For men with confirmed biochemical hypogonadism (morning testosterone <300 ng/dL on two separate occasions) and symptoms of diminished libido, prescription testosterone therapy produces small but significant improvements in sexual function and libido (standardized mean difference 0.35) 1.

Expected Benefits of Prescription Testosterone:

• Clinically meaningful improvement in sexual desire and activity 1
• Small improvement in erectile function (SMD 0.27) 1
• Little to no effect on energy, vitality, physical function, or cognition 1

Formulations Available:

• Transdermal testosterone gel (50-100 mg daily) - provides stable day-to-day levels 4, 5
• Intramuscular testosterone cypionate/enanthate (100-200 mg every 2 weeks) - more economical but higher risk of erythrocytosis 4

Lifestyle Modifications: The Foundation

Before considering any supplements or medications, lifestyle interventions are imperative and have the strongest evidence 3:

Priority Interventions:

• Weight loss in men with obesity - improves testosterone levels in obesity-associated secondary hypogonadism 4, 3
• Adequate sleep - essential for testosterone production 3
• Regular exercise - particularly resistance training 3
• Dietary optimization - whole foods, adequate protein 3

Clinical Algorithm

Step 1: Confirm Diagnosis

• Measure morning total testosterone (8-10 AM) on two separate occasions 4
• Testosterone <300 ng/dL indicates hypogonadism 4
• Measure LH and FSH to distinguish primary from secondary hypogonadism 4

Step 2: Address Reversible Causes

• Implement weight loss if BMI >30 4, 3
• Optimize sleep (7-9 hours nightly) 3
• Initiate resistance training program 3
• Evaluate for medications that suppress testosterone 4

Step 3: Treatment Decision

• If testosterone remains <300 ng/dL after 3-6 months of lifestyle modification AND patient has diminished libido/erectile dysfunction: Consider prescription testosterone therapy 1, 4
• If testosterone is low-normal (300-350 ng/dL) with symptoms: Continue lifestyle modifications; supplements are not recommended 1, 2
• If patient desires fertility: Testosterone therapy is absolutely contraindicated; refer to reproductive endocrinology for gonadotropin therapy 1, 4

Critical Pitfalls to Avoid

• Never recommend supplements based on marketing claims alone - 90% of products make unsupported claims 2
• Never assume supplements are safe - many exceed FDA upper tolerable limits and some ingredients may decrease testosterone 2
• Never use supplements as a substitute for proper diagnosis - two morning testosterone measurements are required 4
• Never start testosterone therapy without confirming the patient does not desire fertility - it causes azoospermia 1, 4
• Never diagnose hypogonadism based on symptoms alone - biochemical confirmation is mandatory 1, 4

The Bottom Line

The European Association of Urology explicitly recommends against testosterone therapy in eugonadal men (normal testosterone levels), even for weight loss, cardiometabolic improvement, cognition, vitality, or physical strength 4. This same principle applies to supplements: if testosterone levels are normal, neither supplements nor prescription therapy will provide benefit 1, 4.

For men with confirmed low testosterone and sexual symptoms, prescription testosterone therapy is the evidence-based treatment, not supplements 1. The use of nutraceuticals, if considered at all, must be personalized by physicians and should only be viewed as potential adjunctive approaches in men with documented deficiencies 3.