Supplements

1. Supplementswell supported · human dataAdded 22 August 2026

   Whey wins the protein league, and gains plateau near 30 to 35 g a day

   Pooling 36 trials in 1,552 people doing resistance training, whey protein added the most lean mass versus placebo, about 1.24 kg on average, with benefits plateauing around 30 to 35 g per day; in adults aged 65 and over, whey's edge narrowed while casein climbed the rankings.

   ⚠What it shows: Fairly solid for whey's edge: results pooled from 36 trials in 1,552 people lifting for at least six weeks. The dose plateau is an exploratory estimate, and the older-adult comparison rests on just nine trials, so those two details deserve the most doubt.Systematic review · Front Nutr

   Full breakdown →Whey protein guide →Protein Intake Calculator →Dose-structure-population interactions of protein supplementation combined with resistance training on body composition: a Bayesian network meta-analysis with dose-response modeling. Front Nutr 2026
2. Supplementswell supported · human dataAdded 22 August 2026

   Creatine plus lifting barely touches body fat

   In adults under 50, adding creatine to resistance training produced a very small 1.19% reduction in body fat percentage but no change in absolute fat mass, across pooled results from 12 trials involving 266 people.

   ⚠What it shows: Solid as pooled evidence goes: 12 trials in 266 adults under 50 all point the same way, but the percentage change was tiny and several of the authors have financial ties to creatine companies, which is worth knowing when reading it.Meta-analysis · Nutrients

   Full breakdown →Creatine monohydrate guide →Creatine Calculator →Resistance Exercise and Creatine Supplementation on Fat Mass in Adults < 50 Years of Age: A Systematic Review and Meta-Analysis. Nutrients 2023
3. Supplementswell supported · human dataAdded 21 August 2026

   Omega-3 lifts adiponectin, the fat-tissue hormone, but leaves leptin alone

   Omega-3 supplementation modestly raised adiponectin, a hormone released by fat tissue, across 52 trials with 4,568 participants, with the clearest gains at doses above 2000 mg daily taken for more than 10 weeks. Leptin, another fat-tissue hormone, did not budge.

   ⚠What it shows: Believable but small: results pooled from 52 trials in 4,568 people showed only a modest rise in adiponectin, and the trials disagreed with each other a lot, so the true size of the effect is uncertain. Leptin showed no effect at all.Meta-analysis · Crit Rev Food Sci Nutr

   Full breakdown →Omega-3 (fish oil) guide →Effect of omega-3 fatty acids supplementation on adipokines: a systematic review and meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr 2022
4. Supplementswell supported · human dataAdded 21 August 2026

   Creatine's strength boost is real but smaller than the tub suggests

   Across 69 randomised trials in 1937 adults, creatine plus resistance training improved bench or chest press strength by 1.43 kg and squat strength by 5.64 kg versus placebo, with gains in vertical jump and peak power too. Benefits were most consistent in younger adults and males, while handgrip and leg press showed no significant improvement.

   ⚠What it shows: About as good as supplement evidence gets: results pooled from 69 trials in 1937 adults. The weaker showing in women and older adults may reflect too few studies rather than no effect, and one author has advised companies that sell creatine.Meta-analysis · Nutrients

   Full breakdown →Creatine monohydrate guide →Creatine Calculator →The Effects of Creatine Supplementation on Upper- and Lower-Body Strength and Power: A Systematic Review and Meta-Analysis. Nutrients 2025
5. Supplementswell supported · human dataAdded 20 August 2026

   Beef protein builds muscle just as well as whey

   Beef protein supplements matched whey for gains in lean mass and changes in fat mass across pooled randomised trials. Compared with no protein at all, beef protein increased daily protein intake, lean body mass and lower-limb strength.

   ⚠What it shows: Solid as far as it goes: results pooled from seven trials with 270 people found the protein source mattered less than getting enough of it. Fat mass and upper-body strength did not clearly improve over no supplement, so the benefits were specific rather than across the board.Meta-analysis · Nutrients

   Full breakdown →Whey protein guide →Protein Intake Calculator →Does Beef Protein Supplementation Improve Body Composition and Exercise Performance? A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients 2019
6. Supplementswell supported · human dataAdded 19 August 2026

   Green tea for weight loss: 1.78 kg is the honest number

   Green tea supplementation reduced body weight by an average of 1.78 kg and BMI by 0.65 kg/m² in a pooled analysis of randomised trials. Waist circumference only fell significantly at doses of at least 800 mg a day or in trials shorter than 12 weeks.

   ⚠What it shows: Believable but modest: results pooled from randomised trials in people with obesity, though the individual studies disagreed with each other and the dose patterns were inconsistent. The average saving was under two kilograms, so this is a nudge, not a transformation.Meta-analysis · Phytother Res

   Full breakdown →Energy balance explained →Calorie Deficit Calculator →The effect of green tea supplementation on obesity: A systematic review and dose-response meta-analysis of randomized controlled trials. Phytother Res 2020
7. Supplementswell supported · human dataAdded 19 August 2026

   Whey beats five rival proteins for ageing muscle

   Whey came top of six protein sources for boosting muscle mass, handgrip strength and walking speed in middle-aged and older adults doing resistance training, in a network analysis pooling 78 randomised trials with 5272 participants.

   ⚠What it shows: A strong signal from results pooled across 78 trials in 5272 middle-aged and older adults, ranking whey against milk, casein, meat, soy and peanut protein. Many participants were hospitalised or living with health conditions, so the ranking may not transfer neatly to healthy trained lifters.Meta-analysis · Nutrients

   Full breakdown →Whey protein guide →Protein Intake Calculator →Comparative Efficacy of Different Protein Supplements on Muscle Mass, Strength, and Physical Indices of Sarcopenia among Community-Dwelling, Hospitalized or Institutionalized Older Adults Undergoing Resistance Training: A Network Meta-Analysis of Randomized Controlled Trials. Nutrients 2024
8. Supplementspreliminary · human dataAdded 18 August 2026

   Pine bark extract shaves points off blood sugar, pressure and cholesterol

   Pooled results from 24 randomised trials in 1594 people suggest pycnogenol, a supplement, may modestly improve several cardiometabolic markers, lowering fasting blood glucose, blood pressure, BMI and LDL cholesterol while raising HDL cholesterol.

   ⚠What it shows: Promising but not settled: results pooled from 24 trials in 1594 people all pointed the same modest way, yet the authors themselves say longer, better-designed trials are needed to confirm the effects and pin down dose and duration.Meta-analysis · Pharmacol Res

   Full breakdown →Metabolic syndrome explained →Heart Age Calculator →Effects of pycnogenol on cardiometabolic health: A systematic review and meta-analysis of randomized controlled trials. Pharmacol Res 2019
9. Supplementspreliminary · human dataAdded 18 August 2026

   Tea's calming amino acid nudges sleep, but only a little

   L-theanine, an amino acid found in tea, modestly improved self-reported sleep quality, sleep onset and next-day function in a meta-analysis pooling 18 randomised trials with 897 participants, though few trials tested it on its own rather than in blends.

   ⚠What it shows: Promising but not proven: results pooled from 18 trials in 897 people showed small improvements that were all self-reported, and few trials tested pure L-theanine rather than mixtures, so it is hard to say the amino acid alone deserves the credit.Meta-analysis · Sleep Med Rev

   Full breakdown →L-theanine guide →Sleep Calculator →The effects of L-theanine consumption on sleep outcomes: A systematic review and meta-analysis. Sleep Med Rev 2025
10. Supplementswell supported · human dataAdded 17 August 2026

    Whey protein does nothing for muscle after menopause unless you lift

    In postmenopausal women, whey protein supplementation boosted biceps curl strength and lower limb lean mass only when paired with resistance training. Taken without training, it showed no significant benefit for strength or lean mass, and was linked to lower dietary protein intake.

    ⚠What it shows: Strong enough to act on the headline point: results pooled from 10 trials in women aged 55 and over, and the benefit appeared only alongside resistance training. Whey moved neither fat mass nor body weight in either group, so this is about muscle, not weight loss.Meta-analysis · Nutrients

    Full breakdown →Whey protein guide →Protein Intake Calculator →Effect of Whey Protein Supplementation in Postmenopausal Women: A Systematic Review and Meta-Analysis. Nutrients 2022
11. Supplementswell supported · human dataAdded 17 August 2026

    CoQ10 lowers muscle-damage markers in the blood, and more seems to do more

    Pooled results from 28 randomised trials in 830 adults suggest coenzyme Q10 supplementation lowers blood markers of exercise-induced muscle damage and oxidative stress, with each extra 100 mg per day linked to bigger reductions.

    ⚠What it shows: Worth noting but not settled: results pooled from 28 trials in 830 adults show blood markers moving, which is not the same as feeling less sore or performing better. Most of the trials were run in Asia, so how far the findings travel is unclear.Meta-analysis · Clin Nutr ESPEN

    Full breakdown →DOMS explained →Recovery Readiness Index →The effects of coenzyme Q10 supplementation on biomarkers of exercise-induced muscle damage, physical performance, and oxidative stress: A GRADE-assessed systematic review and dose-response meta-analysis of randomized controlled trials. Clin Nutr ESPEN 2024
12. Supplementswell supported · human dataAdded 16 August 2026

    Zinc could knock 2.25 days off a common cold

    In pooled results from randomised trials, zinc supplementation taken on its own was linked to colds ending about 2.25 days sooner in healthy adults. Other micronutrients, including vitamin D and vitamins A and E, did not appear to prevent colds or ease symptom severity.

    ⚠What it shows: Worth taking seriously: this sweep of all the trial evidence pooled 10 zinc trials in healthy adults, and the 2.25-day saving appeared only when zinc was taken by itself. The plausible range around that figure is wide, so the exact size of the benefit is not pinned down.Systematic review · Am J Trop Med Hyg

    Full breakdown →Zinc guide →Zinc Supplementation Reduces Common Cold Duration among Healthy Adults: A Systematic Review of Randomized Controlled Trials with Micronutrients Supplementation. Am J Trop Med Hyg 2020
13. Supplementswell supported · human dataAdded 16 August 2026

    Creatine adds strength for older women, especially past 24 weeks

    Pooled data from ten randomised trials in 211 older women show that adding creatine to resistance training improves upper-body strength, with both upper- and lower-body strength improving when programmes lasted at least 24 weeks. Measures of muscle mass did not change.

    ⚠What it shows: Promising but thin: results pooled from ten trials covering just 211 older women, and the authors themselves call for higher-quality studies to confirm it. Strength improved, yet muscle size showed no measurable change.Meta-analysis · Nutrients

    Full breakdown →Creatine monohydrate guide →Creatine Calculator →Efficacy of Creatine Supplementation Combined with Resistance Training on Muscle Strength and Muscle Mass in Older Females: A Systematic Review and Meta-Analysis. Nutrients 2021
14. Supplementswell supported · human dataAdded 16 August 2026

    Nitrate's performance boost vanishes in the fittest athletes

    Across 80 randomised crossover studies in young healthy adults, dietary nitrate supplementation produced a small but clear improvement in exercise performance. The benefit appeared in recreationally active young men but was not observed in women-only studies or in well-trained endurance athletes.

    ⚠What it shows: About as solid as supplement evidence gets for the headline effect, pooling 80 trials, but the boost is small and the studies were mostly of young healthy men. Only six tested women alone, so the blank result in women may simply reflect missing data.Meta-analysis · Med Sci Sports Exerc

    Full breakdown →VO₂max explained →VO2max Calculator →Ergogenic Effect of Nitrate Supplementation: A Systematic Review and Meta-analysis. Med Sci Sports Exerc 2020
15. Supplementswell supported · human dataAdded 16 August 2026

    Beetroot juice can lift endurance, but caffeine may cancel it out

    A systematic review of 23 studies found beetroot juice can improve cardiorespiratory endurance in athletes, increasing efficiency and time to exhaustion at submaximal intensities, though combining it with other supplements such as caffeine may undermine the effect.

    ⚠What it shows: Fairly persuasive but not settled: a sweep of 23 studies in athletes mostly pointed the same way, though the authors note some findings contradict each other. No numbers were pooled, so the size of the benefit is unclear.Systematic review · Nutrients

    Full breakdown →Caffeine guide →VO2max Calculator →Effects of Beetroot Juice Supplementation on Cardiorespiratory Endurance in Athletes. A Systematic Review. Nutrients 2017
16. Supplementswell supported · human dataAdded 16 August 2026

    Soy protein keeps pace with whey for muscle

    Across 19 randomised trials of active people aged 14 to 39, soy protein produced lean mass gains identical to whey in some studies and showed potential endurance performance benefits at doses of 10 to 53.3 g, while its effects on testosterone and cortisol were inconsistent.

    ⚠What it shows: A sweep of all 19 randomised trials on this in active people aged 14 to 39, but the picture is patchy: soy matched whey only in some studies, hormone findings flipped between trials, and results on aerobic capacity conflicted. This is soy holding its own rather than beating whey.Systematic review · Sports Med

    Full breakdown →Whey protein guide →Protein Intake Calculator →Effect of Soy Protein Supplementation on Muscle Adaptations, Metabolic and Antioxidant Status, Hormonal Response, and Exercise Performance of Active Individuals and Athletes: A Systematic Review of Randomised Controlled Trials. Sports Med 2023
17. Supplementspreliminary · human dataAdded 16 August 2026

    Fish oil left blood fats and blood sugar unmoved in diabetes trials

    Pooled results from 11 trials in people with diabetes found omega-3 supplements had no significant effect on triglycerides, cholesterol, HbA1c, fasting glucose or inflammation markers. Fasting insulin, insulin resistance and corneal nerve health did improve, though the authors call these findings hypothesis-generating.

    ⚠What it shows: Take this as a signal, not a verdict: results were pooled from 11 small trials and the reviewers rated the certainty of the evidence as very low to low. The nulls on blood fats and blood sugar are as informative as the insulin finding, but bigger, longer trials are needed before either counts as settled.Review · Curr Dev Nutr

    Full breakdown →Insulin sensitivity explained →Effectiveness of ω-3 Supplementation on Biochemical, Clinical, and Inflammatory Parameters in Patients with Diabetes: A Systematic Review and Meta-analysis. Curr Dev Nutr 2026
18. Supplementswell supported · human dataAdded 16 August 2026

    Creatine's body composition effect is real but small

    Across 143 randomised trials, creatine supplementation increased body mass by 0.86 kg and fat-free mass by 0.82 kg while reducing body fat percentage by 0.28 points; effects were larger when a maintenance dose was used or resistance training was performed alongside.

    ⚠What it shows: About as strong as supplement evidence gets: results pooled from 143 trials where people were assigned at random, with unusually consistent findings. Even so, the average gain was under a kilogram of lean mass, and one author has ties to a creatine manufacturer.Meta-analysis · J Int Soc Sports Nutr

    Full breakdown →Creatine monohydrate guide →Creatine Calculator →Creatine supplementation protocols with or without training interventions on body composition: a GRADE-assessed systematic review and dose-response meta-analysis. J Int Soc Sports Nutr 2024
19. Supplementswell supported · human dataAdded 15 August 2026

    Creatine plus lifting adds 11.35 kg to lower-body strength, in men at least

    In a meta-analysis of 23 trials in adults under 50, creatine combined with resistance training increased upper-body strength by 4.43 kg and lower-body strength by 11.35 kg on average compared with placebo. Men gained significantly in both, while women, who appeared in only a handful of the trials, showed no significant strength gains.

    ⚠What it shows: Strong evidence for men: results pooled from 23 trials consistently showed bigger strength gains when creatine was added to lifting. Women were nearly absent from those trials, so the lack of a clear effect in women may simply reflect too little data rather than a true sex difference.Meta-analysis · Nutrients

    Full breakdown →Creatine monohydrate guide →Creatine Calculator →Effects of Creatine Supplementation and Resistance Training on Muscle Strength Gains in Adults <50 Years of Age: A Systematic Review and Meta-Analysis. Nutrients 2024
20. Supplementspreliminary · human dataAdded 14 August 2026

    Grape seed extract knocked 6 points off systolic blood pressure

    In pooled results from 16 randomised trials totalling 810 people, grape seed extract lowered systolic blood pressure by about 6 mmHg and diastolic by nearly 3 mmHg, with the biggest effects in younger, heavier participants and those with metabolic syndrome.

    ⚠What it shows: Promising but thin: results pooled from 16 trials covering just 810 people in total. The authors themselves call for a large, long-term trial in people with high blood pressure before anyone counts on it.Meta-analysis · Medicine (Baltimore)

    Full breakdown →Metabolic syndrome explained →Heart Age Calculator →The impact of grape seed extract treatment on blood pressure changes: A meta-analysis of 16 randomized controlled trials. Medicine (Baltimore) 2016
21. Supplementspreliminary · human dataAdded 14 August 2026

    Caffeine gives women a small lifting edge, on wobbly evidence

    Pooled results from 24 studies in women show caffeine before resistance exercise slightly improves maximal strength and may boost muscular endurance in some protocols, but the certainty of evidence is low or very low and results vary widely.

    ⚠What it shows: Treat it as a starting point: a sweep of 24 studies in women found small average benefits, but the reviewers rate their own certainty as low or very low. Results swung so much between protocols that no dose, timing or population advice can be drawn from it.Systematic review · Front Physiol

    Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Acute caffeine supplementation and resistance exercise performance in female participants: a systematic review and three-level meta-analysis. Front Physiol 2026
22. Supplementswell supported · human dataAdded 14 August 2026

    Zinc eases insulin resistance, with an LDL catch

    Across 18 pooled trials in 1023 people with diabetes, prediabetes or gestational diabetes, zinc supplements improved insulin resistance and lowered inflammation and oxidative stress markers. But LDL cholesterol rose slightly, by a mean of 3.46, a trade-off whose clinical relevance remains uncertain.

    ⚠What it shows: Reasonably solid on direction: results pooled from 18 trials in 1023 people with diabetes, prediabetes or gestational diabetes. The wrinkle is the mixed cholesterol picture, and nobody yet knows whether the small LDL rise matters in practice.Meta-analysis · Endocrinol Diabetes Metab

    Full breakdown →Insulin sensitivity explained →Effects of Zinc Supplementation on Glycemic Control, Insulin Resistance, Inflammation and Oxidative Stress in Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Endocrinol Diabetes Metab 2026
23. Supplementspreliminary · human dataAdded 14 August 2026

    Astaxanthin helped aerobic performance; the brain benefits didn't show

    Astaxanthin taken alongside regular training enhanced fat oxidation and improved physical performance in a meta-analysis of 11 trials with 346 healthy people, with the clearest gains in aerobic exercise, at doses of 20 mg or more, and beyond 12 weeks of use. Effects on cognitive accuracy were marginal and reaction time did not change.

    ⚠What it shows: Early days: just 11 trials with 346 healthy people in total, and the fatigue signal rests on only two studies, so these estimates could shift a lot once bigger trials arrive.Meta-analysis · Biol Res Nurs

    Full breakdown →Astaxanthin guide →VO2max Calculator →Effects of Astaxanthin Supplementation on Fatigue, Motor Function and Cognition: A Meta-Analysis of Randomized Controlled Trials. Biol Res Nurs 2024
24. Supplementswell supported · human dataAdded 14 August 2026

    Omega-3s improved blood fats and pressure, but LDL didn't budge

    Omega-3 supplementation modestly improved triglycerides, total cholesterol, blood pressure and several inflammatory markers in people with metabolic syndrome and related heart conditions across 48 trials with 8489 participants, while LDL cholesterol was unchanged. Doses of 2 g per day or less looked most beneficial overall.

    ⚠What it shows: Dependable direction, modest size: results pooled from 48 trials with 8489 people who already had metabolic syndrome or heart disease, so the findings may not transfer to healthy adults. The average improvements were real but small.Meta-analysis · Crit Rev Food Sci Nutr

    Full breakdown →Metabolic syndrome explained →Metabolic Fitness Index →Does omega-3 PUFAs supplementation improve metabolic syndrome and related cardiovascular diseases? A systematic review and meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr 2024

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