Pure City Research Key takeaways The strongest ingredient-level evidence is for food, not pills: a dose-response meta-analysis found every 10 g/day increase in dietary fiber was associated with a 10% lower colorectal cancer risk (RR 0.90), and three daily servings of whole grains were linked to a 17% lower risk (RR 0.83). A 47-trial meta-analysis (commissioned by WHO’s … Read more
Key takeaways WHO states about 38% of cancers can currently be prevented by avoiding known risk factors and applying evidence-based prevention strategies — meaningful risk reduction, not a guarantee (WHO cancer fact sheet). IARC classifies alcoholic beverages and processed meat as carcinogenic to humans, and red meat as probably carcinogenic — mainly for colorectal cancer … Read more
Key takeaways Strongest evidence: mild-to-moderate depression — a Cochrane review of 29 trials (5,489 patients) found St John’s Wort more effective than placebo and comparable to standard antidepressants for mild-to-moderate depression, with fewer side effects than SSRIs. Not effective for severe depression, bipolar depression, or as an alternative to prescribed SSRIs for confirmed major depressive … Read more
Key takeaways Best-supported use: statin-associated muscle pain — a meta-analysis of 12 RCTs (575 patients) found CoQ10 (100–200 mg/day) reduced statin-induced myalgia severity by ~30% (Qu et al., J Am Heart Assoc 2018). Moderate evidence: heart failure — the Q-SYMBIO trial (420 patients, 2 years) found 300 mg/day reduced major cardiovascular events by 43% in … Read more
Key takeaways D3 (cholecalciferol) raises and maintains blood 25(OH)D levels more effectively than D2 (ergocalciferol) — a meta-analysis of 24 RCTs confirmed higher potency of D3 per equivalent dose (Tripkovic et al., AJCN). Correcting deficiency (25(OH)D <20 ng/mL) has clear benefit; broad supplementation in already-replete adults for cancer, cardiovascular events, or major fractures showed no … Read more
Key takeaways Best-supported use: pairing 100–200 mg L-theanine with caffeine (50–100 mg) to reduce jitter and improve sustained attention on cognitive tasks — multiple RCTs and one systematic review support the combination effect (Nutritional Neuroscience, Camfield 2014). For acute situational stress and anxiety, small RCTs (200–400 mg) show reductions in self-rated stress and salivary cortisol … Read more
Key takeaways Best-supported use: acute stress and cognitive performance under high-demand conditions (sleep deprivation, cold exposure, multitasking under noise) — military and lab RCTs show 100–150 mg/kg tyrosine restored working memory and reaction time when depleted by stress (Hase et al., Neurosci Biobehav Rev). Works by replenishing dopamine and norepinephrine precursors that get depleted under … Read more
Key takeaways Strongest evidence: correcting low dietary intake, migraine prevention (300–600 mg daily under medical supervision), and modest blood-pressure reduction — with meta-analyses supporting a systolic drop of ~2 mmHg (Cochrane, Journal of Human Hypertension). For sleep, anxiety, muscle cramps, depression, diabetes, and bone health, evidence is mixed to weak — a systematic review found … Read more
Key takeaways Strongest evidence: modest triglyceride reduction (25–30% with 2–4 g/day EPA+DHA) and reduced cardiovascular events in secondary prevention at prescription doses — FDA has approved icosapent ethyl (EPA-only, 4 g) after the REDUCE-IT trial. For primary prevention of heart disease in the general population, effects are modest at best — a large Cochrane review … Read more
Key takeaways Melatonin is a timing signal, not a sedative — strongest evidence is for jet lag (Cochrane: 8 of 10 trials showed benefit; 0.5–5 mg equally effective, higher doses not better) and delayed sleep-wake phase disorder. For chronic adult insomnia, AASM explicitly recommends against it — the recommendation is graded weak based on small … Read more
