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Supplementspreliminary · human dataAdded 21 September 2026
Creatine works in women too, but the effect is small
A multilevel meta-analysis of 34 studies covering 692 female participants found creatine supplementation produced a small overall benefit (Hedges g 0.23), with small effects on performance (g 0.30) and body composition (g 0.24), though the certainty of the evidence was rated low to very low.
What it shows: Encouraging direction, shaky confidence: results pooled from 34 studies covering 692 female participants point to small benefits, but the reviewers rated the certainty low or very low throughout. Protocols and outcomes varied so much that no firm sport-specific conclusion is possible yet.Systematic review · Front Nutr
Full breakdown →Creatine monohydrate guide Creatine Calculator Effects of creatine supplementation on exercise performance, physiological outcomes, and body composition in females engaged in exercise or training: a systematic review and multilevel meta-analysis. Front Nutr 2026
Alcohol & Nicotinewell supported · human dataAdded 21 September 2026
Therapy apps help people cut drinking, but they never beat a human therapist
Pooled results from 65 randomised trials found that digitally delivered cognitive behavioural programmes modestly reduced alcohol and drug consumption and improved some psychosocial outcomes compared with minimal treatment, and cut consumption when added to usual care. They were no more effective than therapist-delivered therapy or other active interventions.
What it shows: Solid but modest: results pooled from 65 trials in adults using alcohol or other drugs, and the average benefit was small, with the studies often disagreeing with each other. The apps matched, rather than beat, therapy delivered by a human.Meta-analysis · JMIR Ment Health
Full breakdown →Digitally Delivered Cognitive Behavioral Interventions for Alcohol and Other Drug Use: Meta-Analysis Across Consumption and Psychosocial Outcomes. JMIR Ment Health 2026
Bones & Jointswell supported · human dataAdded 20 September 2026
The unfashionable back brace holds up in pooled trials
A meta-analysis of 13 randomised trials found that back braces and other lumbar orthoses, worn for two weeks or longer, significantly reduced low back pain and its associated disability.
What it shows: Encouraging but light on detail: results pooled from 13 trials of people with low back pain, and the paper reports that pain and disability improved without saying by how much. Braces were often used alongside other therapies, so the brace alone may not deserve all the credit.Meta-analysis · J Back Musculoskelet Rehabil
Full breakdown →Back Pain Efficacy of orthotic support in mitigating low back pain and disability in low back pain sufferers. J Back Musculoskelet Rehabil 2023
Sleepwell supported · human dataAdded 20 September 2026
Nobody knows how much broken sleep it takes to harm your health
A systematic review of 92 human studies found that while sleep disturbance may be linked to changes in blood pressure, stress hormones, blood sugar and other biomarkers, the certainty of the evidence is very low, and no threshold of disturbance at which harm begins could be identified.
What it shows: The headline here is uncertainty itself: a sweep of 92 human studies on disturbed sleep found possible links to blood pressure, hormones and blood sugar, but the studies disagreed with each other and many were at risk of bias. Nobody can yet say how much disturbance, or for how long, starts to matter.Systematic review · J Sleep Res
Full breakdown →Optimising Your Sleep Environment Sleep Calculator Effect of sleep disturbance on biomarkers related to the development of adverse health outcomes: A systematic review of the human literature. J Sleep Res 2023
Tech & Wearableswell supported · human dataAdded 20 September 2026
Same steps, wildly different counts: device settings swing totals from 73% to 178%
In a meta-analysis of 12 studies of adults, step counts from ActiGraph research monitors varied widely with device model, wear location and filter settings: one model recorded 123% of another's steps on the hip, wrist wear captured more steps than hip wear, and against a reference ankle device counts ranged from 73% to 178% depending on setup.
What it shows: Solid on the main point but about research devices: results pooled from 12 studies of adults wearing ActiGraph monitors, a brand used in research rather than sold on the high street. The exact percentages apply to these devices only, so your own tracker's error will differ.Meta-analysis · Med Sci Sports Exerc
Full breakdown →Steps to Calories Calculator Comparative Analysis of ActiGraph Step Counting Methods in Adults: A Systematic Literature Review and Meta-Analysis. Med Sci Sports Exerc 2024
Metabolic & GLP-1well supported · human dataAdded 19 September 2026
Semaglutide linked to more benign growths, not cancer, in diabetes trials
In pooled data from 19 randomised trials covering 38,160 adults with type 2 diabetes, semaglutide was associated with 19% higher odds of developing any neoplasm and 28% higher odds of benign growths. The link with malignant tumours was not statistically significant.
What it shows: Solid as drug evidence goes: results pooled from 19 trials in 38,160 adults with type 2 diabetes, and the extra risk showed up mainly in benign growths, with the apparent link to cancer small enough that chance cannot be ruled out. Trials ran at most 156 weeks, so risk over decades remains unknown.Systematic review · Front Pharmacol
Full breakdown →GLP-1 explained Risk of neoplasms with semaglutide in patients with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials. Front Pharmacol 2026
Sleeppreliminary · human dataAdded 19 September 2026
An altitude sickness pill shows promise against sleep apnoea
A sweep of 17 randomised trials found acetazolamide, a drug best known for altitude sickness, generally improved overnight oxygen levels and reduced breathing disruptions in sleep apnoea. In obstructive sleep apnoea at low altitude, reported reductions in breathing-event rates ranged from roughly 42 to 69.4%, though effects varied widely by context.
What it shows: Encouraging but not yet a treatment you can count on: the 17 trials disagreed with each other so much that their results could not be combined into one number, and the size of the benefit swung widely between types of apnoea and settings. The reviewers themselves say large, long-term trials are needed to work out dosing and who actually responds.Review · Int Orthod
Full breakdown →Efficacy of acetazolamide in adult sleep apnea: A systematic review of randomized controlled trials. Int Orthod 2026
Supplementspreliminary · human dataAdded 19 September 2026
Chilli pepper supplements barely move your cholesterol
Pooled results from four randomised trials suggest chilli pepper (Capsicum annuum) supplements lowered total cholesterol by about 4.98 mg/dL in adults with metabolic syndrome and related conditions, while triglycerides, HDL cholesterol and LDL cholesterol did not change.
What it shows: Take it lightly: only four trials could be pooled, and the single change found was a small dip in total cholesterol while triglycerides, HDL and LDL all stayed put. Larger trials in people with genuinely raised blood fats are needed before this means much.Meta-analysis · Phytother Res
Full breakdown →Metabolic syndrome explained Heart Age Calculator The effects of Capsicum annuum supplementation on lipid profiles in adults with metabolic syndrome and related disorders: A systematic review and meta-analysis of randomized controlled trials. Phytother Res 2023
Hormonespreliminary · human dataAdded 19 September 2026
Lifting spikes testosterone, but push too long and it dips for days
A review of 15 randomised trials in 251 people maps how acute exercise moves testosterone: lifting raises it more and for longer than cardio, after which levels typically recover within 1 h, while extended high-intensity exercise can suppress testosterone during recovery for up to 72 h as cortisol works against it.
What it shows: Useful as a map rather than a verdict: the 15 trials covered just 251 people between them and were reviewed precisely because earlier results disagreed. Every change described is short-lived, so nothing here shows exercise raising resting testosterone for good.Systematic review · PeerJ
Full breakdown →Cortisol explained Recovery Readiness Index Effect of acute exercise on the dynamics of testosterone levels: a systematic review of randomized controlled trials. PeerJ 2026
Environmentpreliminary · human dataAdded 18 September 2026
No clear link between fine air pollution and ovarian cancer, pooled data show
A pooled analysis found no association between fine particulate air pollution (PM2.5) and ovarian cancer, and only a weak elevation in endometrial cancer risk. Across 145 studies, research on environmental chemicals and these cancers remains sparse.
What it shows: Reassuring but thin: the ovarian result pools just four studies and the endometrial one five, so the picture could shift as more research lands. The authors themselves call the wider literature on these cancers sparse.Review · Environ Res
Full breakdown →Epidemiologic research on environmental chemical exposures and ovarian and endometrial cancers: a systematic review. Environ Res 2026
Longevitywell supported · human dataAdded 18 September 2026
Protein with exercise helps frail older adults regain muscle and speed
Across 22 randomised trials, adding protein supplementation to exercise training improved frailty status, lean mass, leg strength and walking speed in frail older adults. Protein paired with resistance training gave the clearest lean mass gains.
What it shows: Solid for direction, modest in size: results pooled from 22 trials where frail older people were assigned at random to protein plus exercise or a comparison group. Study quality averaged 6.7 out of 10 and the programmes varied, so the best formula is still unsettled.Meta-analysis · Nutrients
Full breakdown →Sarcopenia explained Protein Intake Calculator Effects of Protein Supplementation Combined with Exercise Intervention on Frailty Indices, Body Composition, and Physical Function in Frail Older Adults. Nutrients 2018
Bones & Jointswell supported · human dataAdded 18 September 2026
Your tendon can feel better without looking better on a scan
Exercise therapy for tendinopathy works without the tendon visibly changing: a review of 20 studies in 625 patients found strong evidence refuting structural change as the explanation for improvement after eccentric training. Only heavy-slow resistance training showed moderate evidence of structural change.
What it shows: Strong on what it rules out, silent on what the real mechanism is: a sweep of 20 studies covering 625 tendinopathy patients, though the studies were too varied to pool their numbers. The searches ran to 2012, so newer imaging work could refine the picture.Systematic review · Br J Sports Med
Full breakdown →Eccentric explained Do structural changes (eg, collagen/matrix) explain the response to therapeutic exercises in tendinopathy: a systematic review. Br J Sports Med 2014
Immunitypreliminary · human dataAdded 18 September 2026
Tai Chi cools inflammatory markers, but only a high dose moves all three
Pooled results from nine randomised trials in 571 people suggest Tai Chi lowers the inflammatory marker TNF-alpha, and that IL-6 and CRP also fall when the amount of practice is high. Low amounts of Tai Chi showed little effect on IL-6 and CRP.
What it shows: An early signal, not a verdict: results pooled from nine trials totalling 571 people, which the authors rate as relatively low quality with findings that disagreed with each other. The suggestion it could help in COVID-19 goes well beyond what these trials tested.Meta-analysis · Ann Palliat Med
Full breakdown →Inflammation explained Impact of Tai Chi on CRP, TNF-alpha and IL-6 in inflammation: a systematic review and meta-analysis. Ann Palliat Med 2021
Nutritionwell supported · human dataAdded 18 September 2026
Whole milk, not dairy overall, linked to prostate cancer deaths in men
In pooled data from 11 cohort studies of 778,929 people, total dairy intake was not linked to cancer mortality, but whole milk in men was tied to higher prostate cancer death risk, rising 43% per daily serving.
What it shows: Reassuring on dairy overall, but treat the milk finding with care: these studies followed people rather than testing diets on them, so heavy milk drinkers may differ in other ways. The prostate signal came from a subgroup and only just reached statistical significance.Meta-analysis · Nutr J
Full breakdown →All-cause mortality explained Healthy Lifestyle & Life Expectancy Dairy products intake and cancer mortality risk: a meta-analysis of 11 population-based cohort studies. Nutr J 2016
Gut & Microbiomepreliminary · human dataAdded 18 September 2026
Gut bacteria help predict whose fasting weight loss lasts
A 5-day fast in 38 healthy adults cut body mass index mostly through fat loss, with improvements partially persisting 12 weeks later; a model built on baseline gut microbiome and clinical measures predicted who kept the weight off, and it held up in three independent fasting cohorts.
What it shows: Early but intriguing: one small trial in 38 healthy adults, so the prediction idea needs bigger groups before anyone plans a fast around their gut bacteria. It helps that the model held up in three separate fasting cohorts, including people fasting far longer.RCT · Genome Med
Full breakdown →Gut microbiome explained Calorie Deficit Calculator Machine learning identifies microbiome and clinical predictors of sustained weight loss following prolonged fasting. Genome Med 2026
Bones & Jointswell supported · human dataAdded 18 September 2026
Gentle aerobic exercise eased fibromyalgia pain, no hard intensity needed
Pooled results from 28 randomised trials covering 2,494 people with fibromyalgia found aerobic exercise modestly reduced pain, fatigue, depressed mood and quality-of-life limitations and improved physical fitness. Pain fell with both land-based and water-based exercise of slight to moderate intensity, two or three times per week.
What it shows: About as good as this evidence gets: results pooled from 28 randomised trials in 2,494 people with fibromyalgia, and the improvements held up when the authors tested for bias, though each one was modest in size. Few trials described their exercise programmes in detail, so which format works best is still unresolved.Meta-analysis · Arthritis Res Ther
Full breakdown →Health-related quality of life (HRQoL) explained Heart Rate Zone Calculator Efficacy of different types of aerobic exercise in fibromyalgia syndrome: a systematic review and meta-analysis of randomised controlled trials. Arthritis Res Ther 2010
Recoverywell supported · human dataAdded 17 September 2026
The ice bath beats the cryo chamber for next-day soreness
A meta-analysis of 13 randomised trials in 214 physically active people found cold water immersion relieved delayed onset muscle soreness better than body cryotherapy within 24 hours of strenuous exercise, while cryotherapy showed only a small and fragile edge in jump performance recovery at 24 hours. By 48 hours neither method held a significant advantage.
What it shows: Fairly solid for the soreness result: it pools results from 13 trials of 214 active people, and those trials agreed with each other on soreness. They disagreed on jump performance, so cryotherapy's small edge there deserves little weight.Meta-analysis · Medicine (Baltimore)
Full breakdown →Cold Water Immersion Recovery Readiness Index Effects of cold water immersion vs body cryotherapy on delayed onset muscle soreness and jump performance following acute strenuous exercise in physically active participants: A systematic review and meta-analysis. Medicine (Baltimore) 2026
Alcohol & Nicotinewell supported · human dataAdded 17 September 2026
Alcohol dents working memory, worst on tasks that juggle information
Pooled data from 32 studies of 1629 healthy adults show that acute doses of alcohol produce small to medium impairments in working memory, with the deficits most pronounced on tasks requiring active mental manipulation. The size of the effect varied with dose, task type, the control condition used and the sex mix of the sample.
What it shows: About as solid as lab evidence gets: results pooled from 32 studies covering 1629 healthy adults, and the average study quality was good. These were one-off measured doses in controlled settings, so real-world drinking situations may play out differently.Meta-analysis · Psychopharmacology (Berl)
Full breakdown →Executive function explained Effects of acute alcohol administration on working memory: a systematic review and meta-analysis. Psychopharmacology (Berl) 2022
Gut & Microbiomewell supported · human dataAdded 17 September 2026
Probiotics nudged mood, anxiety and stress in healthy adults
Pooling seven randomised placebo-controlled trials in healthy adults, probiotic supplementation produced a small but statistically significant improvement in symptoms of depression, anxiety and perceived stress compared with placebo.
What it shows: Decent evidence for a small effect: results pooled from seven trials in healthy volunteers, all of which passed a quality check. Everyone studied was healthy, so this says nothing about treating diagnosed depression or anxiety.Meta-analysis · J Altern Complement Med
Full breakdown →Probiotics explained Probiotics and Subclinical Psychological Symptoms in Healthy Participants: A Systematic Review and Meta-Analysis. J Altern Complement Med 2017
Sleeppreliminary · human dataAdded 17 September 2026
Your sleeping pill may still be driving with you the next morning
In pooled driving tests in healthy adults, most sleep medications at approved doses left next-morning driving no worse than placebo. Drugs that did impair it included zolpidem 10 mg, triazolam 0.5 mg, ramelteon 8 mg, daridorexant 100 mg and mirtazapine, while most medications beat zopiclone.
What it shows: Treat this as a useful map, not a verdict: the authors rated their own confidence in the evidence as low or very low. It pools 22 trials of next-morning driving tests, almost all in healthy volunteers rather than people with insomnia.Meta-analysis · Eur Neuropsychopharmacol
Full breakdown →Residual effects of medications for sleep disorders on driving performance: A systematic review and network meta-analysis of randomized controlled trials: NMA driving and hypnotics. Eur Neuropsychopharmacol 2024
Trainingpreliminary · human dataAdded 17 September 2026
Blood flow cuffs made walking build extra muscle and fitness
Pooled results from twelve randomised trials show that adding blood flow restriction cuffs to low or moderate intensity walking produced small to moderate extra gains in cardiovascular fitness, leg strength, muscle size and functional performance compared with identical walking without cuffs.
What it shows: Promising but shaky: results pooled from twelve trials, and cuffed walking beat plain walking on every outcome measured. The authors rate the underlying studies as low to very low quality with a high risk of bias, so the size of these gains deserves caution.Review · J Sports Sci
Full breakdown →Hypertrophy explained VO2max Calculator Effect of blood flow restricted walking on cardiovascular fitness, muscular development, and functional performance in adults: A systematic review with meta-analysis. J Sports Sci 2026
Sleepwell supported · human dataAdded 16 September 2026
The counterintuitive insomnia fix: spend less time in bed
Pooled results from nine randomised trials in 1239 adults found that sleep restriction therapy on its own reduced insomnia severity, shortened the time to fall asleep and improved sleep efficiency, sleep quality and time awake during the night, while cutting total sleep time as the treatment intends. At follow-up the gains in insomnia severity, sleep efficiency and night-time waking held, but faster sleep onset did not.
What it shows: About as solid as insomnia evidence gets in the short term: results pooled from nine trials in 1239 adults all pointed the same way. The wrinkle is durability, since the benefit for falling asleep faster had faded by longer follow-up and total sleep time drops at first by design.Meta-analysis · J Sleep Res
Full breakdown →Optimising Your Sleep Environment Sleep Calculator The Effect of Single-Component Sleep Restriction Therapy for Insomnia in Adults: A Meta-Analysis of Randomised Controlled Trials. J Sleep Res 2026
Metabolic & GLP-1well supported · human dataAdded 16 September 2026
Frequent sitting breaks tame blood sugar; harder ones tackle blood fats
Pooled results from 144 randomised studies in 2216 adults suggest the best way to break up sitting depends on the goal: frequent activity bouts did most for blood glucose, longer or more intense bouts were needed to lower triglycerides, and moderate to vigorous intensity improved blood vessel function. Activity breaks also lowered insulin and both systolic and diastolic blood pressure in these short-term experiments.
What it shows: Convincing for the hours after you move, unproven for the years ahead: results pooled from 144 short lab experiments covering 2216 adults, so whether these acute improvements add up to lasting health benefits was not tested here.Meta-analysis · Eur J Prev Cardiol
Full breakdown →Insulin sensitivity explained Metabolic Fitness Index Optimizing physical activity bouts to interrupt sedentary behaviour for cardiometabolic health: a systematic review and meta-analyses of randomized controlled trials. Eur J Prev Cardiol 2026
Nutritionpreliminary · human dataAdded 16 September 2026
Time-restricted eating gave exercisers a small extra fat loss without costing muscle
Pooled results from 11 trials in 602 adults with overweight or obesity found that adding time-restricted eating to exercise produced modest extra losses of 1.64 kg body weight and 1.30 kg fat mass compared with exercise plus a control diet, without reducing fat-free mass. Insulin resistance also improved, while cholesterol, blood pressure, fasting glucose and HbA1c did not differ between groups.
What it shows: Real but modest: results pooled from 11 trials in 602 adults with overweight or obesity, and the extra losses were measured in single kilograms and centimetres. Most trials were short, so nobody knows whether the edge holds over the long run.Study · Nutr Rev
Full breakdown →Intermittent fasting explained Calorie Deficit Calculator Effects of Time-Restricted Eating Combined with Exercise on Body Composition and Cardiometabolic Health in Adults with Overweight or Obesity: A Systematic Review and Meta-Analysis. Nutr Rev 2026

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