Supplements

1. Supplementswell supported · human dataAdded 8 August 2026

   Supplement users were 2.74 times more likely to report doping

   Across 26 cross-sectional studies of 13,296 athletes, doping was 2.74 times more prevalent among dietary supplement users (14.7%) than non-users (6.7%), and supplement users also reported stronger doping intentions and attitudes.

   ⚠What it shows: All 26 included studies were cross-sectional, so the link is an association and cannot show supplement use causes doping; doping was self-reported and measurement of supplement use was inconsistent across studies.Meta-analysis · Int J Drug Policy

   Full breakdown →Are dietary supplement users more likely to dope than non-users?: A systematic review and meta-analysis. Int J Drug Policy 2023
2. Supplementswell supported · human dataAdded 8 August 2026

   Black seed supplements cooled inflammation markers in metabolic syndrome

   A meta-analysis of 16 randomised controlled trials in 1033 people with metabolic syndrome and related disorders found that Nigella sativa (black seed) supplementation significantly reduced inflammatory markers, CRP, TNF-α and IL-6, and improved oxidative stress markers versus placebo.

   ⚠What it shows: Meta-analysis of 16 RCTs (n=1033) in patients with metabolic syndrome and related disorders; outcomes are blood biomarkers, not disease events, and the authors themselves conclude only that intake 'could be associated' with improvement.Meta-analysis · Curr Pharm Biotechnol

   Full breakdown →Metabolic syndrome explained →Effect of Nigella sativa Intake on Oxidative Stress and Inflammation in Patients with Metabolic Syndrome and Related Disorders: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Curr Pharm Biotechnol 2024
3. Supplementspreliminary · human dataAdded 8 August 2026

   Early review found protein supplement evidence too thin to recommend

   A systematic review of nine randomised trials in healthy people found lean-mass gains of 0.8 to 1.9 kg with protein supplementation during resistance training, but the longest trial lasted only 12 weeks. The authors concluded the evidence did not support recommending protein supplements for healthy individuals.

   ⚠What it shows: Systematic review of only nine RCTs in healthy subjects, searched up to April 2009; only three studies reached level 3 evidence and the longest intervention was 12 weeks, so the conclusion reflects a thin, dated trial base rather than a definitive verdict.Systematic review · Arch Latinoam Nutr

   Full breakdown →Whey protein guide →Protein Intake Calculator →[Effectivity in the use of protein supplements in resistance training: systematic review]. Arch Latinoam Nutr 2010
4. Supplementspreliminary · human dataAdded 6 August 2026

   Pomegranate showed recovery gains in small trials

   A systematic review of 11 studies in 176 athletes and physically active people reported that pomegranate supplementation improved whole-body strength, feelings of vitality, muscle fatigue and soreness, vessel diameter and blood flow, and antioxidant markers, with faster recovery of post-training muscle-damage markers. Doses ranged from 50 ml to 500 ml over 7 days to 2 months.

   ⚠What it shows: Narrative systematic review of 11 studies published 2010-2018 with just 176 participants in total, 155 of them male; no meta-analysis was performed, and supplement form, dose (50 ml-500 ml) and duration (7 days-2 months) varied so widely that results cannot be pooled or a dose inferred.Systematic review · Int J Vitam Nutr Res

   Full breakdown →DOMS explained →Effect of pomegranate fruit supplementation on performance and various markers in athletes and active subjects: A systematic review. Int J Vitam Nutr Res 2021
5. Supplementspreliminary · human dataAdded 6 August 2026

   Your caffeine boost may hinge on one gene

   Across 19 randomised trials with 732 participants using caffeine doses of 2 to 9 mg/kg, performance benefits were most consistent in people carrying the CYP1A2 AA genotype, smaller in AC carriers, and null or even detrimental in those with the CC genotype, though the studies did not all agree.

   ⚠What it shows: Systematic review of 19 RCTs in 732 athletes and physically active people published 2012-2024, with no meta-analysis and no consensus between studies; 84% of the included trials were rated as raising 'some concerns' for risk of bias and only two were low risk.Systematic review · Nutr Res

   Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Influence of the CYP1A2 genotype on the exercise performance of physically active individuals under caffeine supplementation: a systematic review. Nutr Res 2025
6. Supplementswell supported · human dataAdded 6 August 2026

   Moderate caffeine dose beat low dose in time trials

   Pooling 48 randomised placebo-controlled trials (689 healthy adults), low caffeine doses of ≤3 mg·kg-1 shortened aerobic time-trial completion time (SMD -0.27), while moderate doses of 4-6 mg·kg-1 produced a larger and more consistent effect (SMD -0.52). No eligible trial reporting time-to-completion tested doses above 6 mg·kg-1.

   ⚠What it shows: Meta-analysis of 48 randomised placebo-controlled trials in healthy adults aged 18-59 using acute oral anhydrous caffeine, but only 689 participants in total, effects pooled as standardised mean differences across varied time-trial protocols, and no trials of doses above 6 mg·kg-1 met the inclusion criteria, so the top of the dose range remains untested for this outcome.Meta-analysis · Nutrients

   Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Dose-Response Effect of Oral Caffeine Use on Aerobic Exercise Performance: A Systematic Review and Meta-Analysis. Nutrients 2026
7. Supplementswell supported · human dataAdded 6 August 2026

   BCAA supplements added little to resistance training

   In a meta-analysis of 12 randomised trials (459 older adults with sarcopenia), adding branched-chain amino acid-rich supplements to resistance training improved only skeletal muscle index (SMD 0.337, p = 0.029). Grip strength, walking speed, chair-stand performance, SPPB score, knee extension strength, total lean mass and fat mass showed no significant advantage.

   ⚠What it shows: Meta-analysis of 12 randomised trials with only 459 participants in total, all older adults with sarcopenia; the one positive outcome had a confidence interval reaching close to zero and several functional measures pointed in inconsistent directions, so this cannot be read across to younger or healthy trainees.Meta-analysis · Arch Gerontol Geriatr

   Full breakdown →Sarcopenia explained →Protein Intake Calculator →Effects of branched-chain amino acid-rich nutritional supplements combined with resistance training on body composition and body function in older patients with sarcopenia. Arch Gerontol Geriatr 2026
8. Supplementswell supported · human dataAdded 6 August 2026

   HMB added nothing on top of resistance training

   Across 13 randomised trials of 561 adults aged 50 and over, adding HMB to resistance training produced no significant benefit for fat mass (SMD 0.24), muscle mass (SMD 0.05) or muscle strength (SMD 0.04). The authors concluded it cannot be recommended as a routine adjunct for people able to do structured exercise.

   ⚠What it shows: Meta-analysis of 13 randomised trials totalling 561 adults aged 50 and over; heterogeneity was high for the strength outcomes and trial durations and doses varied, and the findings say nothing about people unable to train or about younger lifters.Meta-analysis · Age Ageing

   Full breakdown →Sarcopenia explained →Protein Intake Calculator →Efficacy of HMB supplementation as an adjunct to resistance training in older adults: a comprehensive meta-analysis. Age Ageing 2026
9. Supplementspreliminary · human dataAdded 6 August 2026

   Creatine's edge may not carry to elite athletes

   A critical review of the creatine literature concluded that the supplement's performance benefits have generally been shown in untrained people doing several exercise bouts under laboratory conditions, while the limited data available on highly trained athletes performing single competition-like tasks showed no benefit. The authors judged that widespread creatine use to improve competition performance was not justified on that evidence, though repeated-effort sports remained a plausible unconfirmed case.

   ⚠What it shows: A narrative critical review from 1997, not a modern pooled analysis: it rests on a small body of studies in highly trained athletes, reports no effect sizes, and says nothing about creatine's use during training blocks or in non-athletes.Meta-analysis · Int J Sports Med

   Full breakdown →Creatine monohydrate guide →Creatine Calculator →Creatine supplementation as an ergogenic aid for sports performance in highly trained athletes: a critical review. Int J Sports Med 1997
10. Supplementswell supported · human dataAdded 6 August 2026

    Probiotics nudged spine bone density, not bone markers

    Pooling randomised trials, probiotic supplementation produced small increases in lumbar spine areal bone mineral density (+0.010) and hip aBMD (+0.022 g/cm2), with no significant effect on femoral neck density or on the bone turnover markers P1NP and CTX. Most included trials were in postmenopausal women.

    ⚠What it shows: Systematic review and meta-analysis of randomised trials (16 comparisons for lumbar spine, 9 for hip, 7 for femoral neck), mostly in postmenopausal women, with moderate-to-high heterogeneity throughout; the hip effect became non-significant when key trials were removed, and no fracture outcomes were pooled.Meta-analysis · Osteoporos Int

    Full breakdown →Probiotics guide →Probiotic Supplementation and Bone Health Parameters in Adults: A Systematic Review and Meta-Analysis. Osteoporos Int 2026
11. Supplementswell supported · human dataAdded 6 August 2026

    Vitamin D's cold-fighting effect shrinks in big trials

    A critical review with meta-analysis found that vitamin D's apparent protection against acute respiratory infections was confined to small trials: the summary odds ratio was 0.69 in trials of 25 to fewer than 248 patients but 0.98 in trials of 248 to 16,000 patients (interaction p = 0.0001), with strong evidence of publication bias.

    ⚠What it shows: A meta-analysis of previously published randomised trials, not new experimental data; the acute respiratory infection trials were re-analysed from an earlier pooled dataset, and the analysis splits trials by size, which can be confounded by differences in populations, doses and outcome definitions. It shows the benefit signal is fragile, not that vitamin D is useless for people who are deficient.Meta-analysis · PLoS One

    Full breakdown →Vitamin D guide →Vitamin D, acute respiratory infections, and Covid-19: The curse of small-size randomised trials. A critical review with meta-analysis of randomised trials. PLoS One 2025
12. Supplementspreliminary · human dataAdded 1 August 2026

    Ketone drink raised ketones but not race performance

    Adding 1,3-butanediol to a carbohydrate drink roughly doubled circulating ketones in male athletes long adapted to a ketogenic diet, but time-trial performance was no better than carbohydrate alone. Lactate, substrate oxidation, oxygen consumption, perceived exertion and heart rate were also unchanged.

    ⚠What it shows: A counterbalanced crossover trial in just 9 recreationally active men with at least a year of ketogenic adherence; the authors stress this is too small to prove no effect, only that none was detectable here.RCT · Nutrients

    Full breakdown →Ketogenic diet explained →Acute 1,3-Butanediol Co-Ingestion with Carbohydrate Does Not Improve Endurance Performance in Chronically Ketogenic Male Athletes. Nutrients 2026
13. Supplementspreliminary · human dataAdded 30 July 2026

    CoQ10 beat taurine on muscle-damage markers

    In a 14-day randomised trial in under-19 footballers, CoQ10 (300 mg/day) lowered markers of oxidative stress, muscle damage and cortisol more than taurine, while taurine raised the anti-inflammatory marker IL-10 more; both blunted the drop in immune markers. These were blood markers only, with eight players per group.

    ⚠What it shows: Randomised, double-blind, placebo-controlled but very small: 24 male under-19 soccer players, only 8 per group, 14 days, and outcomes were circulating biomarkers with no performance or recovery measures. The authors call the findings preliminary and pending confirmation in larger trials.RCT · Nutrients

    Full breakdown →Cortisol explained →Recovery Readiness Index →Practical Nutritional Strategies to Attenuate Physiological Stress in Adolescent Soccer Players: A Comparative Trial of CoQ10 and Taurine. Nutrients 2026
14. Supplementswell supported · human dataAdded 30 July 2026

    Beetroot juice lifts VO2max, but mostly in amateurs

    Across 38 placebo-controlled trials in 703 healthy adults, beetroot juice produced a small but significant improvement in VO2max/VO2peak (SMD 0.24). The gain was clearer in recreationally active people (SMD 0.38) and not clearly demonstrated in highly trained athletes (SMD 0.07).

    ⚠What it shows: Meta-analysis of 38 randomised and crossover trials, 703 healthy adults; effects are small, funnel-plot asymmetry suggested small-study bias and the pooled estimate shrank to 0.19 after adjustment. Certainty rated moderate.Systematic review · Front Nutr

    Full breakdown →VO₂max explained →VO2max Calculator →Effects of beetroot juice supplementation on maximal oxygen uptake during aerobic exercise: a systematic review and meta-analysis. Front Nutr 2026
15. Supplementspreliminary · human dataAdded 30 July 2026

    Beetroot shot nudged leg torque, but not at top speed

    In a crossover trial, 13 physically active men produced greater peak torque and relative peak power on isokinetic knee extension at 60 and 180 degrees per second after beetroot juice containing 800 mg of nitrate than after placebo. Nothing changed during the faster 240 degrees per second fatigue protocol, and muscle EMG and post-exercise lactate were unchanged.

    ⚠What it shows: One small randomised, double-blind, placebo-controlled crossover trial in 13 physically active young men using isokinetic dynamometry, not free-weight lifting; mechanisms unexplained and replication needed.RCT · Nutrients

    Full breakdown →Creatine monohydrate guide →One-Rep Max Calculator →Effects of Acute Dietary Nitrate Supplementation on Selected Isokinetic Performance Variables in Physically Active Men. Nutrients 2026
16. Supplementspreliminary · human dataAdded 29 July 2026

    Omega-3 moved lipids and blood pressure, not kidney function

    Genetically predicted higher plasma omega-3 levels were associated with a lower risk of diabetic kidney disease (odds ratio 0.869), while omega-6 showed no significant association; a paired meta-analysis of 12 randomised trials (474 participants) found omega-3 supplementation lowered triglycerides, systolic blood pressure and a kidney injury marker, but did not improve albumin-to-creatinine ratio or estimated glomerular filtration rate.

    ⚠What it shows: Genetic (Mendelian randomisation) analysis plus a meta-analysis of 12 small trials totalling only 474 participants in people with diabetic kidney disease; mediation findings were nominally significant only, and hard kidney-function outcomes did not shift.Study · FASEB J

    Full breakdown →Blood pressure explained →Metabolic Fitness Index →The Impact of Omega Fatty Acids on DKD: A Multimodal Study Integrating Mendelian Randomization, Proteomic Mediation Analysis, and Meta-Analysis. FASEB J 2026
17. Supplementspreliminary · human dataAdded 29 July 2026

    High-dose fish oil AF risk limited to high-risk patients

    An updated meta-analysis of 35 randomised trials including 114 592 people found that new-onset atrial fibrillation risk rose only in participants at high cardiovascular risk taking more than 1500 mg/d of EPA/DHA (odds ratio 1.43, absolute risk difference 0.8%). Lower doses showed no significant increase, even in high-risk groups.

    ⚠What it shows: Pooled randomised trial data are strong, but this is a subgroup-defined finding across 35 heterogeneous trials in people aged 50 and over, with published and unpublished data combined; the authors call for prospective studies weighing the risk against omega-3's benefits.Study · Circ Arrhythm Electrophysiol

    Full breakdown →Omega-3 (fish oil) guide →Heart Age Calculator →Effects of Omega-3 Fatty Acid Treatment on Risk for Atrial Fibrillation: An Updated Meta-Analysis of 35 Trials including 114 592 Individuals. Circ Arrhythm Electrophysiol 2026
18. Supplementspreliminary · human dataAdded 29 July 2026

    Herbal blend for male ageing symptoms loses to placebo

    In a 12-week randomised, double-blind trial in 70 men aged 45-75 with male climacteric symptoms, a botanical formulation of Elaeagnus multiflora fruit and Cynanchum wilfordii extracts at 1500 mg/day was no better than placebo: symptom scores fell substantially in both arms with no significant difference between them.

    ⚠What it shows: One 12-week trial, 70 men randomised and 64 analysed per protocol; single formulation and dose, short follow-up, and long-term safety cannot be judged from it.Study · Medicina (Kaunas)

    Full breakdown →Testosterone →A Randomized Double-Blind Placebo-Controlled Trial of a Botanical Formulation for Symptom Management in Male Climacteric Syndrome. Medicina (Kaunas) 2026
19. Supplementspreliminary · human dataAdded 29 July 2026

    Probiotic cut 1.20 kg, but not BMI or cholesterol

    Pooling 17 randomised trials in non-diabetic overweight or obese adults, Lactobacillus plantarum supplementation modestly reduced body weight (-1.20 kg) and waist circumference (-1.36 cm) but did not significantly change BMI, blood lipids, fasting glucose, insulin, inflammatory markers or liver enzymes.

    ⚠What it shows: Meta-analysis of 17 RCTs in non-diabetic overweight or obese adults; effects are small, heterogeneity was high for BMI (I²=82.8%), and GRADE certainty limited benefits beyond weight and waist.Review · Probiotics Antimicrob Proteins

    Full breakdown →Visceral fat explained →Body Fat Calculator →Efficacy of Lactobacillus plantarum on Body Composition, Lipid Profile, Liver Enzymes, and Inflammatory Markers in Overweight or Obese Adults: A GRADE Systematic Review and Meta-analysis of Randomized Trials. Probiotics Antimicrob Proteins 2026
20. Supplementspreliminary · human dataAdded 29 July 2026

    Taurine plus training beat training alone in obese men

    A four-arm trial in 44 men with obesity found that 12 weeks of combined aerobic-resistance training plus 3 g/day taurine produced the biggest shifts: body mass -5.50 kg, body fat -4.90%, lower asprosin and higher spexin. Training alone or taurine alone did less, and the untreated control group changed on nothing.

    ⚠What it shows: Four-arm randomised trial with only n=11 per group in men with a BMI of at least 30; supplement-blinded rather than fully double-blind, and the authors themselves call the results preliminary and exploratory pending larger replication.Study · Nutrients

    Full breakdown →Taurine guide →Combined Aerobic-Resistance Training and Taurine Supplementation Reduce Asprosin and Elevate Spexin in Men with Obesity: A 12-Week Supplement-Blinded, Randomized Controlled Trial. Nutrients 2026
21. Supplementswell supported · human dataAdded 29 July 2026

    Creatine adds muscle, but far less than the hype

    A meta-analysis of 10 randomised trials using direct muscle imaging found that adding creatine to resistance training produces only a very small extra increase in muscle size compared with training plus placebo. Gains in upper- and lower-body muscle thickness were in the region of 0.10-0.16 cm.

    ⚠What it shows: Meta-analysis of 10 RCTs (44 outcomes) in healthy adults; the pooled effect was very small and its credible interval crossed zero; several authors declared ties to the creatine industry.Meta-analysis · Nutrients

    Full breakdown →Creatine monohydrate guide →Creatine Calculator →The Effects of Creatine Supplementation Combined with Resistance Training on Regional Measures of Muscle Hypertrophy: A Systematic Review with Meta-Analysis. Nutrients 2023
22. Supplementswell supported · human dataAdded 29 July 2026

    Whey protein improves muscle in sarcopenic older adults

    In a meta-analysis of 10 randomised trials with 1,154 participants, whey protein supplementation improved muscle mass and gait speed in older adults diagnosed with sarcopenia, and combining it with resistance training significantly increased handgrip strength.

    ⚠What it shows: Meta-analysis of 10 RCTs (1,154 older adults with diagnosed sarcopenia, community and hospital settings mixed); the authors say more studies are needed to validate the results.Meta-analysis · J Nutr Health Aging

    Full breakdown →Whey protein guide →Protein Intake Calculator →Improving sarcopenia in older adults: a systematic review and meta-analysis of randomized controlled trials of whey protein supplementation with or without resistance training. J Nutr Health Aging 2024
23. Supplementspreliminary · human dataAdded 27 July 2026

    Whey plus collagen outperformed whey alone

    In an 8-week randomised trial, resistance-trained men taking 30 g/day whey protein plus 10 g/day collagen gained more muscle mass, lumbar spine bone density and strength than whey alone, collagen alone or placebo.

    ⚠What it shows: Small double-blind RCT: 40 resistance-trained men across four groups, so about 10 per arm, over only 8 weeks; muscle mass came from bioelectrical impedance rather than a criterion method, and the reported gains, including the spine bone density change, are unusually large and unusually consistent for such a short trial, so independent replication matters.Study · BMC Sports Sci Med Rehabil

    Full breakdown →Whey protein guide →Protein Intake Calculator →The combined effects of whey protein and collagen supplementation on bone mineral density and muscle mass in resistance-trained men: a randomized controlled trial. BMC Sports Sci Med Rehabil 2026
24. Supplementspreliminary · human dataAdded 27 July 2026

    Mint-family herbs trimmed BMI and waist, not body fat

    Pooling 20 randomised trials in 2,445 adults with metabolic syndrome or related conditions, supplements from the mint and sage family produced modest reductions in BMI, weight, waist circumference and waist-to-hip ratio. Directly measured body fat mass did not change significantly.

    ⚠What it shows: Meta-analysis of 20 RCTs (n=2,445) in adults with metabolic syndrome, obesity, type 2 diabetes, dyslipidaemia or fatty liver; half the trials had unclear allocation concealment, 10% had high performance bias risk, trials were short, body fat was measured indirectly, and the genus-level signals for Salvia and Zataria came from few trials.Review · J Ethnopharmacol

    Full breakdown →Metabolic syndrome explained →Body Fat Calculator →Impact of Lamiaceae plants on anthropometric indices in patients with metabolic syndrome: A systematic review and meta-analysis of randomized clinical trials. J Ethnopharmacol 2026

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