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1. Supplementspreliminary · human dataAdded 10 August 2026

   NAC boosted exercise performance in men but left inflammation untouched

   In a systematic review of 16 controlled trials in adult men, N-acetylcysteine (NAC) supplementation improved exercise performance, antioxidant capacity and glutathione status with no serious side effects reported, but showed no clear benefit for blood markers, inflammation or measures of muscle behaviour.

   ⚠What it shows: Promising but far from settled: a sweep of all the studies turned up 16 controlled trials in adult men, most reporting benefits, but the results were never pooled into a single number and the authors themselves call for more research. Women were not studied, so nothing here applies to them yet.Systematic review · Nutrients

   Full breakdown →NAC (N-acetylcysteine) guide →Influence of N-Acetylcysteine Supplementation on Physical Performance and Laboratory Biomarkers in Adult Males: A Systematic Review of Controlled Trials. Nutrients 2023
2. Skin & Glow-upwell supported · human dataAdded 10 August 2026

   Collagen supplements really did smooth wrinkles in pooled trials

   Oral hydrolysed collagen taken for 90 days reduced wrinkles and improved skin hydration and elasticity compared with placebo in a meta-analysis of 19 randomised, double-blind trials with 1,125 participants aged 20 to 70, 95% of them women.

   ⚠What it shows: Stronger than most supplement claims: results pooled from 19 placebo-controlled trials in 1,125 people, where neither participants nor researchers knew who got the real thing. Almost all participants were women aged 20 to 70, so the evidence says little about men.Meta-analysis · Int J Dermatol

   Full breakdown →Collagen explained →Effects of hydrolyzed collagen supplementation on skin aging: a systematic review and meta-analysis. Int J Dermatol 2021
3. Sleepwell supported · human dataAdded 10 August 2026

   Exercise eased menopausal insomnia most where sleep was worst

   Exercise programmes significantly reduced insomnia severity and eased sleep problems in menopausal women in a meta-analysis of randomised trials, with the clearest effects in women who already had sleep disorders. Overall sleep quality scores did not improve significantly.

   ⚠What it shows: Encouraging but uneven: results pooled from ten trials where women were assigned at random showed less insomnia but no clear change in overall sleep quality scores, and the underlying studies carried a moderate risk of bias. The review also could not tell which type or length of exercise works best.Systematic review · Front Med (Lausanne)

   Full breakdown →Optimising Your Sleep Environment →Sleep Calculator →The effect of exercise intervention on improving sleep in menopausal women: a systematic review and meta-analysis. Front Med (Lausanne) 2023
4. Hormoneswell supported · human dataAdded 10 August 2026

   Thyroid trouble may not be the anxiety driver it's made out to be

   Across 12 population-based studies of 676,658 people, links between thyroid problems and anxiety were small and mostly not statistically significant. Only an overactive thyroid showed a modest significant association.

   ⚠What it shows: Take the uncertainty seriously: this pools 12 population studies of 676,658 people, the most representative evidence yet, but the studies disagreed with each other, so anything from a modest link to no link at all remains possible.Meta-analysis · PeerJ

   Full breakdown →Thyroid disorders, thyroid autoimmunity, and anxiety-a systematic review and meta-analysis of population-based studies. PeerJ 2026
5. Nutritionpreliminary · human dataAdded 10 August 2026

   Three daily servings of full-fat dairy left weight and cholesterol untouched

   Adding three daily servings of full-fat dairy for 12 weeks left body weight, fat mass and fasting cholesterol unchanged in 74 adults with overweight or obesity, even with no calorie restriction. The group eating it freely also saw small falls in hip circumference and systolic blood pressure.

   ⚠What it shows: Reassurance rather than a green light: one 12-week trial in 74 adults with overweight, showing full-fat dairy did no harm rather than that it helps. The dairy groups also ate more protein and calcium, which muddies what caused the small benefits.RCT · J Nutr

   Full breakdown →Energy balance explained →Calorie Deficit Calculator →The Effect of Three Daily Servings of Full-Fat Dairy for 12 Weeks on Body Weight, Body Composition, Energy Metabolism, Blood Lipids, and Dietary Intake of Adults with Overweight and Obesity. J Nutr 2026
6. Hormonespreliminary · human dataAdded 10 August 2026

   Testosterone therapy cleared of raising heart attack and stroke risk

   In a trial of 5246 men aged 45 to 80 with low testosterone and high cardiovascular risk, testosterone gel did not increase major cardiac events compared with placebo, with events in 7.0% versus 7.3%. Atrial fibrillation, acute kidney injury and pulmonary embolism were more common with testosterone.

   ⚠What it shows: About as solid as single-trial safety evidence gets: 5246 men with low testosterone and existing heart risk were assigned at random to testosterone gel or placebo and followed for nearly three years on average. It shows no extra heart attacks or strokes, not that testosterone helps, and clots, heart rhythm problems and kidney injury were more common on treatment.RCT · N Engl J Med

   Full breakdown →Testosterone explained →Heart Age Calculator →Cardiovascular Safety of Testosterone-Replacement Therapy. N Engl J Med 2023
7. Sleepwell supported · human dataAdded 10 August 2026

   Aerobic exercise outdoes traditional Chinese exercise for student sleep

   Pooled results from 21 randomised trials in 1252 university students with sleep problems found both traditional Chinese exercises and general aerobic exercise improved sleep, with aerobic exercise the more effective of the two. Effects were largest with sessions of 40 to 60 minutes, done 3 to 5 times a week.

   ⚠What it shows: Strong for students, unknown beyond them: results pooled from 21 trials covering 1252 university students, all with existing sleep problems. The trials disagreed with each other enough that the best session length and frequency should be read as a rough guide, not a prescription.Meta-analysis · Medicine (Baltimore)

   Full breakdown →Sleep Calculator →Comparing the efficacy of traditional Chinese exercises and general aerobic exercises in university students with sleep disorders: A systematic review and meta-analysis. Medicine (Baltimore) 2024
8. Mindpreliminary · human dataAdded 10 August 2026

   A cortisol pill threw men's inner GPS off course

   A single 20 mg dose of cortisol markedly impaired path integration, the ability to keep track of your own position while moving, in 39 healthy men tested under both cortisol and placebo, and diminished grid-like activity in the entorhinal cortex on brain scans.

   ⚠What it shows: Interesting but early: 39 healthy men were each tested under both cortisol and a placebo in a lab, so it says nothing yet about women, real-world stress or repeated exposure. The dose came from a pill, not from stress itself.Study · PLoS Biol

   Full breakdown →Cortisol explained →Cortisol treatment impairs path integration and alters grid-like representations in the male human entorhinal cortex. PLoS Biol 2026
9. Mindpreliminary · human dataAdded 10 August 2026

   Good stress is not the opposite of bad stress

   In a pre-registered study of 251 UK adults rating 20 real-life challenges, eustress, the positive experience of stress, behaved as a measurable trait: nine processes such as successful outcomes, fulfilment and positive affect explained a median 83% of the variance in how positive a challenge felt, and it was unrelated to trait distress.

   ⚠What it shows: Useful groundwork rather than a life hack: 251 UK adults rated challenging situations in one pre-registered survey, so it maps what good stress looks like without testing how to create it. Everything rests on self-report.Study · Soc Indic Res

   Full breakdown →Successful Outcomes, Fulfilment, and Positive Affect: Establishing Facets of Eustress Across Real-Life Challenging Situations. Soc Indic Res 2026
10. Cardiopreliminary · human dataAdded 9 August 2026

    150 minutes a week buys less heart protection than you think

    In a cohort of 17,088 UK adults with activity trackers, meeting the 150 minutes a week guideline was linked to a modest 8%-9% lower cardiovascular disease risk; a reduction beyond 30% required roughly 560-610 minutes a week.

    ⚠What it shows: Worth weight but not proof of cause: this is an observational study of 17,088 UK adults who wore activity trackers, with genetic analyses pointing the same way for fitness. Activity was measured once, and Biobank volunteers tend to be healthier than the general population.Study · Br J Sports Med

    Full breakdown →VO₂max explained →VO2max Calculator →Joint non-linear dose-response associations of device-measured physical activity and cardiorespiratory fitness with cardiovascular disease: a cohort and Mendelian randomisation study. Br J Sports Med 2026
11. Cardiowell supported · human dataAdded 9 August 2026

    Energy drinks push blood pressure up mid-workout

    A meta-analysis of 21 randomised trials found that caffeinated energy drinks raised systolic blood pressure by 9.02 mmHg and heart rate by 2.86 bpm during exercise in healthy adults, while diastolic blood pressure was unchanged.

    ⚠What it shows: Solid pooled evidence, but a narrow window on it: 21 randomised trials covering just 296 healthy adults, mostly men, during aerobic exercise only. The data were too thin to say anything about heart rhythm effects, which is the question many readers will actually have.Meta-analysis · Appl Physiol Nutr Metab

    Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Effects of caffeinated energy drinks on cardiovascular responses during exercise in healthy adults: a systematic review and meta-analysis of randomized controlled trials. Appl Physiol Nutr Metab 2022
12. Sleeppreliminary · human dataAdded 9 August 2026

    Phone addiction tracks with worse sleep in young adults

    A meta-analysis pooling 63 observational studies found a moderate correlation (r=0.38) between smartphone addiction and poor sleep quality in adults aged 18 to 25, alongside later sleep onset, shorter sleep and more daytime dysfunction.

    ⚠What it shows: Consistent but correlational: nearly all the underlying studies were cross-sectional and self-reported, so poor sleepers may simply reach for their phones more, not the reverse. The pooled link was moderate and results varied enormously between studies.Review · Int J Adolesc Med Health

    Full breakdown →Optimising Your Sleep Environment →Sleep Calculator →Smartphone addiction and sleep disruption among young adults (18-25 years): a systematic review and meta-analysis. Int J Adolesc Med Health 2026
13. Sleepwell supported · human dataAdded 9 August 2026

    Late-night hard training doesn't ruin sleep after all

    A meta-analysis of 15 trials found that high-intensity exercise finishing 2 to 4 hours before bedtime did not disrupt nighttime sleep in healthy adults; the only significant change was a small 2.34% reduction in REM sleep.

    ⚠What it shows: A trustworthy pooled result built from small studies: 15 trials totalling just 194 healthy good sleepers aged 18 to 50. It says nothing about people who already sleep badly, or about sessions finishing very close to lights out.Meta-analysis · Sleep Med Rev

    Full breakdown →HIIT explained →Sleep Calculator →The effects of evening high-intensity exercise on sleep in healthy adults: A systematic review and meta-analysis. Sleep Med Rev 2021
14. Women's Healthpreliminary · human dataAdded 9 August 2026

    Lifting weights may cool inflammation after menopause

    Across 12 randomised trials in 482 menopausal and postmenopausal women, resistance training reduced C-reactive protein, a blood marker of inflammation, by a mean of 0.47 mg/dL, though the reviewers rated the evidence as very low quality.

    ⚠What it shows: Treat this as a promising signal rather than a settled result: 12 randomised trials in 482 women pointed the same way, but the reviewers themselves graded the evidence very low quality, citing study flaws, inconsistency and possible publication bias. They state plainly that the true effect could be substantially different.Meta-analysis · Menopause

    Full breakdown →Inflammation explained →Strength Standards →Effects of resistance training on C-reactive protein in menopausal and postmenopausal women: a systematic review and meta-analysis of randomized controlled trials. Menopause 2022
15. Trainingwell supported · human dataAdded 9 August 2026

    Different workouts fight different kinds of inflammation

    A network meta-analysis of 75 randomised trials in 4048 women with overweight and obesity found each exercise type topped a different inflammatory marker: resistance training ranked best for lowering C-reactive protein, aerobic exercise for TNF-α, combined training for interleukin-6 and leptin, and HIIT for raising adiponectin.

    ⚠What it shows: Strong on breadth, weaker on head-to-head certainty: the rankings pool 75 trials with 4048 participants, but network meta-analysis compares exercise types partly indirectly, across studies rather than within them. The winner for one marker was not the winner for another, so no single verdict emerges.Meta-analysis · J Sci Med Sport

    Full breakdown →HIIT explained →Heart Rate Zone Calculator →Comparative efficacy of different exercise types on inflammatory markers in women with overweight and obesity: A systematic review and network meta-analysis of randomized controlled trials. J Sci Med Sport 2024
16. Sleepwell supported · human dataAdded 9 August 2026

    The weights room doubles as a sleep aid

    A systematic review of 13 randomised trials found that regular resistance training improves all aspects of sleep, with the greatest benefit for sleep quality, and also improves anxiety and depression.

    ⚠What it shows: A credible review of a thin evidence base: just 13 trials, and the sleep benefit shrank when lifting was combined with aerobic work rather than done on its own. What a single session does to that night's sleep remains poorly studied and inconsistent.Systematic review · Sleep Med Rev

    Full breakdown →Optimising Your Sleep Environment →Sleep Calculator →The effect of resistance exercise on sleep: A systematic review of randomized controlled trials. Sleep Med Rev 2018
17. Supplementswell supported · human dataAdded 9 August 2026

    Folic acid nudges one inflammation marker down, and leaves two others untouched

    Folic acid supplementation lowered C-reactive protein by 0.59 mg/L on average versus placebo across 12 randomised trials, with higher doses linked to lower CRP. It had no significant effect on the inflammatory markers IL-6 or TNF-α.

    ⚠What it shows: Solid pooled evidence, but for a modest effect on a single marker: 12 randomised trials found CRP fell while two other inflammatory markers did not move. Whether a slightly lower CRP reading translates into better health is a question this analysis cannot answer.Meta-analysis · Nutrients

    Full breakdown →Vitamin B9 (folate / folic acid) guide →Effects of Folic Acid Supplementation on Inflammatory Markers: A Grade-Assessed Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials. Nutrients 2021
18. Mindpreliminary · human dataAdded 9 August 2026

    Exercise matched cognitive therapy for depression, but the trials were shaky

    In a systematic review of 14 randomised trials, exercise reduced symptoms of depression compared with no treatment and performed similarly to cognitive therapy. Every included trial had important methodological weaknesses, so the true size of the effect remains uncertain.

    ⚠What it shows: Treat the numbers loosely: all 14 pooled trials had serious flaws, most recruited community volunteers scored on a questionnaire rather than diagnosed patients, and effects looked bigger in trials with shorter follow-up. The reviewers themselves concluded that effectiveness could not be firmly determined.Meta-analysis · BMJ

    Full breakdown →Meta-analysis explained →The effectiveness of exercise as an intervention in the management of depression: systematic review and meta-regression analysis of randomised controlled trials. BMJ 2001
19. Cardiowell supported · human dataAdded 9 August 2026

    Yoga drops blood pressure and cholesterol, but no more than ordinary exercise

    A meta-analysis of 32 randomised trials found yoga improved cardiovascular risk factors versus non-exercise controls, including systolic blood pressure down 5.21 mmHg and LDL cholesterol down 12.14 mg/dl, but showed no significant advantage over conventional exercise.

    ⚠What it shows: A large pooled analysis pointing one way, but built on small, mixed trials of moderate quality, so the exact sizes of the improvements are soft. Yoga beat doing nothing across the board, yet it did not outperform ordinary exercise, and blood sugar measures did not improve.Meta-analysis · Eur J Prev Cardiol

    Full breakdown →Metabolic syndrome explained →Heart Age Calculator →The effectiveness of yoga in modifying risk factors for cardiovascular disease and metabolic syndrome: A systematic review and meta-analysis of randomized controlled trials. Eur J Prev Cardiol 2016
20. Women's Healthwell supported · human dataAdded 9 August 2026

    Mindfulness and dance eased menopausal sleep and mood in 18 trials

    Across 18 randomised trials involving 1,572 perimenopausal and postmenopausal women, mind-body therapies such as mindfulness, music therapy, dance and yoga produced moderate-to-large improvements in sleep quality, depression and anxiety compared with usual care or no intervention.

    ⚠What it shows: As strong as this area gets: a meta-analysis of 18 randomised trials in 1,572 women, with robust sensitivity checks and no sign of publication bias. The comparisons were usual care or nothing at all, so part of the benefit may come from the attention and routine rather than the practice itself.Meta-analysis · Front Public Health

    Full breakdown →Sleep Calculator →Mind-body therapies for sleep disturbances, depression, and anxiety in menopausal women: a systematic review and meta-analysis of randomized controlled trials. Front Public Health 2025
21. Women's Healthwell supported · human dataAdded 9 August 2026

    Vibration plates protect ageing bones, but only against doing nothing

    A meta-analysis of nine trials in 527 postmenopausal women found whole body vibration treatments improved bone mineral density at the hip and spine compared with no intervention. When vibration was added to an exercise programme, the extra benefit was negligible.

    ⚠What it shows: Reasonably solid for the headline result: a meta-analysis pooling nine trials in 527 postmenopausal women. But the trials varied hugely in vibration settings, doses and posture, and the right level of stimulation has still not been defined.Meta-analysis · PLoS One

    Full breakdown →Bone density explained →Whole Body Vibration Treatments in Postmenopausal Women Can Improve Bone Mineral Density: Results of a Stimulus Focussed Meta-Analysis. PLoS One 2016
22. Mindpreliminary · human dataAdded 8 August 2026

    In Antarctic isolation, more contact meant more friction, not comfort

    Over a 10-month Antarctic overwintering at Concordia Station, 12 crew members reported progressively rising loneliness and conflict while cohesion and individual performance declined. More frequent close-range contact was associated with more conflict and paranoid thoughts, not with social support.

    ⚠What it shows: Observational study of a single 12-person crew over one 10-month mission; associations only, small sample, and findings from an extreme environment may not generalise to everyday settings.Study · Proc Natl Acad Sci U S A

    Full breakdown →Social interactions in isolated, confined, and extreme environments: A study of Antarctic winter teams using wearable sensors. Proc Natl Acad Sci U S A 2026
23. Sleeppreliminary · human dataAdded 8 August 2026

    Ultrasound sleep patch lengthened REM in a 28-participant study

    A skin-attached patch that pairs focused ultrasound with overnight brainwave recording, aimed at the subthalamic nucleus, increased REM duration by 4.6% and reduced REM latency by 24% in a 28-participant study.

    ⚠What it shows: One 28-participant registered study of a prototype device, reported by the engineering team that developed it and has filed a patent; the abstract gives no daytime outcomes, no safety data and no independent replication.Clinical trial · Nat Commun

    Full breakdown →REM sleep explained →Sleep Calculator →Skin-attached bioadhesive patch enabling ultrasound deep brain stimulation and real-time electrophysiological monitoring for REM sleep enhancement. Nat Commun 2026
24. Metabolic & GLP-1well supported · human dataAdded 8 August 2026

    Semaglutide's weight effect holds up in Asian adults, pooled trials find

    In a meta-analysis of five randomised trials in 2614 Asian adults with overweight or obesity, once-weekly semaglutide 2.4 mg reduced body weight by 8.20% more than placebo, with smaller waist circumference, BMI and systolic blood pressure alongside mostly mild gastrointestinal side effects.

    ⚠What it shows: Pooled data from five placebo-controlled RCTs (2614 Asian adults with overweight or obesity), all rated low risk of bias, but heterogeneity was high for weight, waist and BMI (I2 = 84%, 84% and 66%) and long-term and real-world outcomes were not assessed.Meta-analysis · Diabetes Obes Metab

    Full breakdown →Visceral fat explained →Calorie Deficit Calculator →Efficacy and safety of once-weekly subcutaneous semaglutide 2.4 mg for the management of overweight or obesity in Asian populations: A systematic review, meta-analysis and meta-regression of randomised trials. Diabetes Obes Metab 2025

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