Total and free testosterone increase across 4 RCTs
TestFACTOR® is backed by four published, gold-standard randomized, double-blind, placebo-controlled clinical studies demonstrating consistent testosterone elevation. The most recent study (2024) in 60 recreationally active men aged 40–65 showed a 19% increase in total testosterone and 30–40% increase in free testosterone at 325 mg/day — the most clinically significant free testosterone increase documented for a botanical ingredient.
Sexual function improvement — desire, frequency, and pleasure
The fourth clinical study specifically targeting sexual health confirmed TestFACTOR® significantly enhanced overall sexual function including sexual desire, frequency of sexual activity, sexual pleasure, and other key sexual function metrics vs. placebo. These real-world sexual wellness outcomes are rarely documented in clinical trials for testosterone support ingredients, making TestFACTOR®'s evidence base exceptionally strong for this application.
Reduced fatigue and improved energy
The sexual health study also documented significant reductions in both mental and physical fatigue with TestFACTOR® supplementation — consistent with testosterone's established role in energy regulation, motivation, and physical capacity. This fatigue-reducing benefit extends the ingredient's value beyond sexual wellness into broader men's vitality and active aging applications.
Grip strength improvement
Improved grip strength was confirmed in clinical assessment — providing an objective physical performance measure alongside subjective sexual wellness outcomes. Grip strength is a validated biomarker of overall physical vitality and metabolic health, and its improvement with TestFACTOR® reflects the broad anabolic and vitality-enhancing effects of optimized testosterone levels.
LH stimulation and Leydig cell testosterone biosynthesis enhancement
Sphaeranthus indicus bioactives (sesquiterpene lactones including 7-hydroxyfrullanolide) stimulate hypothalamic-pituitary LH (luteinizing hormone) secretion — the primary hormonal signal driving testicular Leydig cell testosterone synthesis. Mangifera indica bark polyphenols (mangiferin, norathyriol) enhance cholesterol side-chain cleavage enzyme (CYP11A1) activity in Leydig cells, improving the efficiency of testosterone biosynthesis from cholesterol. This dual upstream stimulation (LH signaling) and downstream enhancement (biosynthetic enzyme activity) explains TestFACTOR®'s consistent testosterone elevation across multiple clinical trials.
Randomized, double-blind, placebo-controlled 8-week trial of TestFACTOR® (325 mg/day) in 60 healthy recreationally active men aged 40–65. Primary outcome: sexual function composite score. Secondary: total and free testosterone, fatigue, grip strength.
60 men aged 40–65, BMI 22–29.9, testosterone ≥300 ng/dL. 8-week RCT.
TestFACTOR® significantly improved overall sexual function composite score, desire, frequency, and pleasure vs. placebo. 19% total testosterone increase, 30–40% free testosterone increase. Significant reduction in mental and physical fatigue. Grip strength improved. Well-tolerated across 8 weeks.
Three prior randomized, double-blind, placebo-controlled trials across dose levels and populations documenting consistent testosterone, strength, and endurance benefits.
Multiple male populations across three studies.
Consistent increases in total and free testosterone across all three prior studies. Strength and endurance improvements paralleling the RipFACTOR® sports nutrition studies. Testosterone:cortisol ratio consistently improved favoring anabolism. Four total RCTs confirm reproducible testosterone and performance benefits.