The evidence supports zinc's role in reducing cold duration and its importance for immune and reproductive health. However, more research is needed on optimal dosing and long-term effects.
Recommended intakes / safety / interactionsGeneral population · Government evidence reviewModerate
ODS fact sheet summarizes intakes, deficiency, & risks from excess zinc.
Common cold durationAdults with naturally acquired common cold · Meta-analysis of RCTsModerate
Meta-analysis of 7 placebo-controlled trials (zinc lozenges >75 mg/day) found cold duration was 33% shorter in zinc groups overall; zinc acetate lozenges reduced duration by 40% & zinc gluconate by 28%. No benefit was seen from doses above 100 mg/day.
Men's Sperm Quality & Testosterone Stack
Male factor infertility accounts for ~50% of cases & is largely driven by oxidative stress, micronutrient deficiency, & suboptimal testosterone. Ashwagandha has RCT evidence for significantly improving sperm concentration, motility, & testosterone. L-carnitine is the most evidence-backed intervention for sperm motility. CoQ10 & selenium reduce seminal oxidative damage, while zinc is essential for spermatogenesis & androgen synthesis.
Hair + Nails Reality Check Stack
Minimalist approach that focuses on likely gaps & avoids mega-dosing trends.
Forms & usage▾
Take 15–30 mg daily, preferably with food.