science & studies

An RCT showing that maca increased sexual desire in healthy men after 8 weeks of treatment, without affecting testosterone levels. An important foundational study establishing maca's effect on libido independent of hormonal changes.

A double-blind RCT in patients with mild erectile dysfunction showing improved sexual function and general wellbeing after maca supplementation.

A pilot study examining maca as a treatment for SSRI-induced sexual dysfunction. Results showed a dose-related improvement in sexual function, particularly libido.

A study in postmenopausal women showing that maca reduced anxiety, depression, and sexual dysfunction — independent of estrogen or androgen levels.

A comprehensive review summarizing the evidence for maca's effects on sexual function, fertility, and energy.

An RCT specifically in women showing that standardized fenugreek extract significantly increased sexual desire and arousal.

A double-blind RCT in healthy menstruating women. The Libifem extract increased estradiol and free testosterone and significantly improved sexual function compared to placebo.

An RCT showing that fenugreek extract (Furosap) increased free testosterone by over 45% in male volunteers.

A study examining fenugreek's effect on hormone profiles including testosterone and DHT. Demonstrates the mechanism behind the ingredient's hormonal influence.

A systematic review and meta-analysis demonstrating fenugreek's metabolic effects. Supports the ingredient's safety profile and broad health effects.

An RCT showing that oral L-citrulline improved erection hardness in men with mild ED. Half of the participants went from a hardness score of 3 to 4 (normal).

A meta-analysis of RCTs confirming that L-citrulline lowers blood pressure through improved nitric oxide production and vascular function.

A pharmacokinetic study showing that oral L-citrulline raises plasma arginine and nitric oxide metabolites more effectively than L-arginine directly.

A dose-response study mapping the optimal doses of L-citrulline to maximize nitric oxide production.

A comprehensive review of L-citrulline's roles in vascular health, nitric oxide synthesis, physical performance, and immune function.

A systematic review and meta-analysis specifically on saffron's effect on sexual dysfunction. Found significant improvement, including in antidepressant-induced dysfunction.

An RCT showing that saffron significantly improved erectile function compared to placebo after 10 days.

A double-blind, placebo-controlled RCT showing that saffron significantly reduced PMS symptoms. Directly relevant to women's hormonal health.

A meta-analysis confirming saffron's antidepressant effect with a large effect size compared to placebo. Supports the ingredient's role in mood and wellbeing.

A double-blind RCT comparing saffron with imipramine (an antidepressant) and finding equivalent efficacy in mild to moderate depression.

A Cochrane systematic review (2023) with 50 RCTs and over 8,800 participants showing that cranberry products reduce the risk of UTIs in women, children, and people with recurrent infections.

A systematic review and meta-analysis (2020) confirming that cranberry significantly reduces the risk of recurrent UTIs in otherwise healthy women.

An RCT (JAMA 2014) with 185 older women examining the effect of cranberry capsules on bacteriuria and pyuria.

A review article explaining how proanthocyanidins (PACs) in cranberry prevent E. coli bacteria from adhering to the urinary tract lining.

A double-blind RCT showing that cranberry extract significantly reduces bacterial adhesion of E. coli to urinary tract cells in healthy women.

An RCT in young women showing that GOS supplementation reduces systemic inflammation and microbial translocation — relevant to hormonally linked intimate health.

A review article describing how GOS selectively stimulates the growth of Bifidobacterium and Lactobacillus — the same bacteria that maintain a healthy vaginal flora.

A double-blind RCT showing that daily GOS supplementation significantly increases Bifidobacterium levels in the gut flora of healthy adults.

A preclinical study showing that GOS inhibits intestinal colonization by uropathogenic E. coli — important since the gut's E. coli reservoir is the main source of UTIs.

A double-blind RCT with 159 participants showing that GOS supplementation protects against pathogenic diarrhea by strengthening the gut flora.

A comprehensive review of zinc's role in the immune system showing that zinc supplementation improves immune cell function and reduces susceptibility to infection. EFSA-approved: immune function, cell division.

A comprehensive review summarizing vitamin C's role in collagen synthesis, antioxidant protection, and immune support. EFSA-approved: immune function, collagen formation, oxidative stress.

A systematic review summarizing 11 studies with 805 patients. Oral collagen supplementation showed significant improvement in skin elasticity, hydration, and reduction of wrinkles.

A double-blind, placebo-controlled RCT with 69 women (aged 35–55). 8 weeks of daily collagen peptide intake significantly increased skin elasticity.

A double-blind RCT with 114 women (aged 45–65). 2.5 g of collagen peptides over 8 weeks reduced eye wrinkles and increased procollagen type I and elastin production.

A systematic review and meta-analysis of RCTs confirming that oral collagen intake improves skin hydration, elasticity, and reduces wrinkles.

A double-blind study showing that daily intake of collagen hydrolysate increased facial skin moisture and elasticity and reduced visible signs of aging.

A randomized, double-blind, placebo-controlled study showing that oral intake of hyaluronic acid (120 mg/day) significantly increased skin moisture after 6 weeks.

A double-blind study with 60 participants. Oral intake of hyaluronic acid over 12 weeks reduced wrinkle depth and improved skin radiance and suppleness.

A 12-month RCT showing that oral hyaluronic acid is absorbed systemically and can affect tissues from within, supporting the mechanism behind skin hydration.

A review article explaining hyaluronic acid's central role in skin aging and how reduced HA production leads to dryness, wrinkles, and loss of elasticity.

A comprehensive review evaluating the evidence for biotin in hair loss. Biotin supplementation shows a clear effect in cases of biotin deficiency. EFSA-approved: hair, skin, mucous membranes.

A study showing that 2.5 mg of biotin daily over 6–15 months increased nail thickness by 25% in patients with brittle nails.

A study of 541 women with hair loss showing that 38% had a biotin deficiency. Supports the rationale for biotin supplementation in a hair-focused product.

A comprehensive review of vitamin E's role in dermatology. Summarizes the evidence for antioxidant protection against UV damage and improved wound healing. EFSA-approved: oxidative stress.

A classic review describing vitamin E's mechanism in skin cells — protecting cell membranes from free radicals and supporting the skin's natural barrier function.

A study examining the synergistic antioxidant effect of vitamins C and E on skin aging. The combination provided better protection against UV-induced oxidative stress.

An RCT showing that daily intake of tomato paste (16 mg lycopene/day) for 10 weeks reduced UV-induced erythema by 40%. One of the most cited studies on lycopene and sun protection.

A clinical study in which participants followed a lycopene-rich diet for 12 weeks. Results showed a significant increase in the skin's resistance to UV radiation.

An RCT confirming that lycopene-rich tomato extract protects against UV-induced skin damage, including reduced MMP-1 expression (an enzyme that breaks down collagen).

A systematic review compiling evidence for carotenoids as systemic sun protection. A significant protective effect against UV erythema after 7–10 weeks of intake.

A meta-analysis showing that lycopene supplementation improves the skin's resistance to UV radiation and reduces biomarkers of oxidative stress.

A controlled study showing that beta-carotene (30 mg/day) over 10 weeks provided significant protection against sunburn, measured as reduced erythema intensity.

A systematic review showing that supplementation with at least 15 mg/day of beta-carotene for 10+ weeks provides measurable UV protection.

A review of intervention studies with antioxidants. The combination of beta-carotene with other carotenoids provides better sun protection than single antioxidants.

A systematic review identifying beta-carotene as one of the most effective carotenoids for raising the MED (minimal erythema dose).

A clinical study showing that oral supplementation with vitamin C combined with vitamin E significantly reduced the sunburn reaction after UV exposure. EFSA-approved: collagen formation, oxidative stress.

A review showing that vitamin C stimulates collagen synthesis in the dermis and counteracts age-related collagen breakdown.

A clinical review of copper's biological role in skin health, including melanin synthesis (pigmentation), collagen cross-linking, and wound healing. EFSA-approved: pigmentation, connective tissue.

A review describing copper's biochemical role as a cofactor for tyrosinase, the central enzyme in melanin production.

A randomized, double-blind, placebo-controlled study showing that PHGG significantly reduces IBS-D symptoms including bloating and stool frequency.

A systematic review summarizing the evidence for PHGG in IBS and showing consistent improvement in bloating, abdominal pain, and irregular bowel movements.

A clinical trial showing that PHGG has a prebiotic effect by selectively increasing Bifidobacterium and short-chain fatty acids.

A study showing that daily PHGG supplementation improves constipation symptoms and restores a more balanced gut flora.

A meta-analysis of 9 RCTs showing that peppermint is significantly more effective than placebo at reducing abdominal pain and IBS symptoms. The NNT was 3.

An RCT showing that peppermint oil significantly reduces abdominal pain, bloating, and IBS severity compared to placebo after 4 weeks of treatment.

A double-blind RCT with 110 IBS patients showing that peppermint significantly improves abdominal pain, bloating, and bowel patterns over 8 weeks.

An updated systematic review and meta-analysis (2019) confirming that peppermint is superior to placebo for global symptom relief and abdominal pain in IBS.

A review article summarizing calcium's broad physiological roles including enzyme activation and digestive function. EFSA-approved: normal function of digestive enzymes.

A classic review article mapping the biological mechanism behind zinc's effect on the immune system, cell division, and wound healing. EFSA-approved: immune function, cell division.

A pioneering review by Ananda Prasad documenting the effects of zinc deficiency on immune function, cell division, and growth.