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1. Nutritionwell supported · human dataAdded 18 August 2026

   The weight lost on time-restricted eating was mostly lean mass, not fat

   Pooled studies found time-restricted eating produced a 2.32% weight loss in overweight and obese adults, but the loss came mainly from lean mass rather than fat mass, and LDL cholesterol rose in the fasting groups.

   ⚠What it shows: Worth taking seriously but not as settled: results pooled from randomised trials and some studies that did not assign people at random, in overweight and obese adults. The authors themselves urge caution for anyone with high cholesterol or already low muscle mass.Meta-analysis · Crit Rev Food Sci Nutr

   Full breakdown →Sarcopenia explained →Body Fat Calculator →Missing puzzle pieces of time-restricted-eating (TRE) as a long-term weight-loss strategy in overweight and obese people? A systematic review and meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr 2023
2. Sleeppreliminary · human dataAdded 18 August 2026

   Fasting diets leave sleep largely untouched

   Across 16 randomised trials in adults with overweight or obesity, alternate-day fasting, time-restricted eating and the 5:2 diet left overall sleep quality scores no different from ordinary dieting or a usual diet, with only slight delays in falling asleep on some measures.

   ⚠What it shows: Reassuring but thin: 16 trials pooled together, most of them small and run on different fasting schedules, so the slight delays in falling asleep could easily wash out with better data. The authors themselves call for more careful studies.Meta-analysis · Nutr Metab Cardiovasc Dis

   Full breakdown →Intermittent fasting explained →The effect of intermittent fasting on sleep in adults with overweight or obesity: a network meta-analysis of randomized controlled trials. Nutr Metab Cardiovasc Dis 2026
3. Bones & Jointswell supported · human dataAdded 18 August 2026

   Exercise still eases chronic low back pain after 60

   Exercise therapy meaningfully reduced pain and disability and improved both physical and mental quality of life in adults aged 60 and over with chronic low back pain, across 18 randomised trials involving 989 people. Effects on mobility were less certain.

   ⚠What it shows: Strong enough to matter: results pooled from 18 trials in 989 adults aged 60 and over, and the included studies were of relatively high quality. The mobility findings were shakier and the authors say more trials are needed to confirm them.Meta-analysis · J Orthop Surg Res

   Full breakdown →Back Pain →Effects of exercise therapy on disability, mobility, and quality of life in the elderly with chronic low back pain: a systematic review and meta-analysis of randomized controlled trials. J Orthop Surg Res 2023
4. Trainingwell supported · human dataAdded 17 August 2026

   Strength work cuts sports injuries by roughly two thirds

   Strength training is powerful injury prevention: across trials in 7738 athletes aged 12 to 40, structured strength work cut acute and overuse sports injuries to roughly a third of the risk, and every 10% increase in strength training volume trimmed injury risk by more than four percentage points.

   ⚠What it shows: About as solid as sports science gets: results pooled from six trials that assigned 7738 athletes aged 12 to 40 at random, with consistent findings, high compliance and no sign that negative results were left unpublished. The programmes and sports varied a lot, so no single routine was proven to be the best one.Meta-analysis · Br J Sports Med

   Full breakdown →Training volume explained →Training Volume Calculator →Strength training as superior, dose-dependent and safe prevention of acute and overuse sports injuries: a systematic review, qualitative analysis and meta-analysis. Br J Sports Med 2018
5. Metabolic & GLP-1well supported · human dataAdded 17 August 2026

   Blood sugar falls further once exercise tops 150 minutes a week

   In adults with type 2 diabetes, structured exercise training was associated with a 0.67% drop in HbA1c versus control, and programmes over 150 minutes per week were linked to a 0.89% reduction against 0.36% for shorter ones. Advice to be active was only associated with lower HbA1c when paired with dietary advice.

   ⚠What it shows: Strong by weight of numbers: results pooled from 47 trials with 8538 people with type 2 diabetes, all lasting at least 12 weeks. The trials varied a great deal in design and populations, so the percentage drops are averages across very different programmes rather than a guarantee for any one person.Meta-analysis · JAMA

   Full breakdown →Insulin sensitivity explained →Metabolic Fitness Index →Physical activity advice only or structured exercise training and association with HbA1c levels in type 2 diabetes: a systematic review and meta-analysis. JAMA 2011
6. Women's Healthwell supported · human dataAdded 17 August 2026

   Heavy lifting three times a week strengthens post-menopause bones

   Resistance training improved bone mineral density at the lumbar spine, femoral neck and total hip in a pooled analysis of 17 trials with 690 postmenopausal women. Training at 70% of one-rep max or heavier, three times a week, sustained for 48 weeks or more, looked like the most effective pattern.

   ⚠What it shows: Encouraging but not the final word: results pooled from 17 trials that assigned 690 postmenopausal women at random showed clear gains at the spine and hip, but the trials disagreed with each other considerably at those sites. The ideal mix of intensity and frequency comes from smaller subgroup comparisons, so hold that part loosely.Meta-analysis · J Orthop Surg Res

   Full breakdown →Bone density explained →One-Rep Max Calculator →Optimal resistance training parameters for improving bone mineral density in postmenopausal women: a systematic review and meta-analysis. J Orthop Surg Res 2025
7. Tech & Wearablesnot supported · human dataAdded 17 August 2026

   Weight-loss apps barely shift the scales after a year

   Weight-loss smartphone apps showed no clear benefit in a sweep of 18 trials with 2703 adolescents and adults with overweight or obesity: at 12 months apps made little to no difference to body weight or BMI compared with minimal support, and results at 24 months looked no better.

   ⚠What it shows: A thorough sweep of all the studies, 18 trials and 2703 people, found no convincing benefit, though certainty ranged from moderate down to very low because the apps varied enormously in features and content. With 34 more trials under way, the verdict could still shift within a couple of years.Meta-analysis · Cochrane Database Syst Rev

   Full breakdown →Energy balance explained →Calorie Deficit Calculator →Mobile health (m-health) smartphone interventions for adolescents and adults with overweight or obesity. Cochrane Database Syst Rev 2024
8. Sleepwell supported · human dataAdded 17 August 2026

   Lost sleep hits endurance hardest past the 30 minute mark

   Sleep deprivation cuts endurance performance by a moderate amount, according to pooled results from 31 studies of 478 people, and efforts lasting more than 30 minutes suffer most. One night of total sleep loss and one or more nights of partial loss compromised performance to a similar degree.

   ⚠What it shows: Consistent enough to take seriously: results pooled from 31 controlled studies with 478 healthy people all pointed the same way, though most studies had unclear risk of bias. Whether elite and professional endurance athletes are hit the same way is still unknown.Meta-analysis · Eur J Sport Sci

   Full breakdown →Optimising Your Sleep Environment →Sleep Calculator →How much does sleep deprivation impair endurance performance? A systematic review and meta-analysis. Eur J Sport Sci 2023
9. Longevitypreliminary · human dataAdded 17 August 2026

   Ageing walkers trade push-off power for ankle stability

   Older walkers increasingly brace the ankle by tensing the shin and calf muscles together early in each step, yet produce weaker push-off. In 107 healthy adults aged 26 to 86, ageing was linked to this stability-first strategy that sacrifices propulsion and efficiency.

   ⚠What it shows: A snapshot comparison rather than a study that followed people as they aged: 107 healthy adults aged 26 to 86 were each measured walking once, so it shows how gait differs with age, not why it changes or whether training can reverse it.Study · Gait Posture

   Full breakdown →Sarcopenia explained →Ageing alters ankle mechanics and muscle co-contraction patterns across the gait cycle. Gait Posture 2026
10. Trainingpreliminary · human dataAdded 17 August 2026

    Training close to failure grows muscle but adds no extra strength

    A pooled analysis across resistance training studies found that muscle growth improved as sets were taken closer to failure, while strength gains were similar across a wide range of repetitions in reserve.

    ⚠What it shows: Take it as a strong steer rather than a settled rule: how close to failure lifters actually trained had to be estimated from each study's write-up, and the authors themselves call the analysis exploratory. The trend for muscle growth was consistent, but the exact best stopping point is still unclear.Meta-analysis · Sports Med

    Full breakdown →Hypertrophy explained →Training Volume Calculator →Exploring the Dose-Response Relationship Between Estimated Resistance Training Proximity to Failure, Strength Gain, and Muscle Hypertrophy: A Series of Meta-Regressions. Sports Med 2024
11. Trainingwell supported · human dataAdded 17 August 2026

    Strength training makes highly trained runners more efficient

    In pooled results from controlled trials in 93 highly trained middle- and long-distance runners, adding strength and plyometric training 2-3 times per week for 8-12 weeks produced a large improvement in running economy.

    ⚠What it shows: A strong and consistent pooled result, but built on only five controlled trials covering 93 runners, so the single best programme design is not pinned down. Every participant was a high-level competitive runner, so the size of the benefit for everyday runners is untested here.Meta-analysis · J Strength Cond Res

    Full breakdown →VO₂max explained →Running Pace Calculator →Effects of Strength Training on Running Economy in Highly Trained Runners: A Systematic Review With Meta-Analysis of Controlled Trials. J Strength Cond Res 2016
12. 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
13. Women's Healthwell supported · human dataAdded 17 August 2026

    From yoga to weights, exercise lifts menopausal sleep and mood

    Across 13 randomised trials in 1,470 perimenopausal and postmenopausal women, exercise of many forms, from aerobic work and yoga to Pilates, resistance training, stretching and relaxation, significantly improved sleep quality and psychological well-being.

    ⚠What it shows: Broadly trustworthy on direction, less certain on size: a sweep of all the trials on this covered 13 trials and 1,470 women, but the results were not pooled into a single number, so how big the benefit is remains unclear. Trial quality also varied across the included studies.Systematic review · Menopause

    Full breakdown →Perimenopause explained →Sleep Calculator →Menopause and movement: exercise for better sleep and psychological well-being-a systematic review. Menopause 2025
14. Women's Healthpreliminary · human dataAdded 17 August 2026

    Swimming may strengthen postmenopausal spines, if you do enough of it

    Pooled results from five small trials in 263 women suggest swimming may improve lumbar spine bone mineral density in postmenopausal women, but only when swimming time was between 3 and 6 hours; below 3 hours there was no effect.

    ⚠What it shows: Treat this as a lead, not a verdict: results pooled from just five trials with 263 women in total, and the studies disagreed with each other on the spine result. The authors themselves say the benefit needs further confirmation.Meta-analysis · Biomed Res Int

    Full breakdown →Bone density explained →Swimming as Treatment for Osteoporosis: A Systematic Review and Meta-analysis. Biomed Res Int 2020
15. Trainingwell supported · human dataAdded 17 August 2026

    Lifting weights alone moved blood sugar, insulin and waistlines in type 2 diabetes

    Across 18 randomised trials in 1180 adults with type 2 diabetes and overweight or obesity, resistance training alone improved waist size, fasting glucose, fasting insulin, glycated haemoglobin, HDL cholesterol and triglycerides compared with standard care without exercise.

    ⚠What it shows: As strong as exercise evidence gets: results pooled from 18 trials in 1180 adults with type 2 diabetes and excess weight, all assigned at random. The certainty of the underlying evidence still ranged from very low to moderate, so the exact size of each benefit is uncertain.Meta-analysis · Br J Sports Med

    Full breakdown →Insulin sensitivity explained →Metabolic Fitness Index →Impact of resistance training on cardiometabolic health-related indices in patients with type 2 diabetes and overweight/obesity: a systematic review and meta-analysis of randomised controlled trials. Br J Sports Med 2025
16. 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
17. Metabolic & GLP-1well supported · human dataAdded 17 August 2026

    Tirzepatide beats older GLP-1 drugs for weight loss, at a gut-side-effect cost

    In a pooled analysis of 12 randomised trials with 11,758 participants, tirzepatide reduced body weight, BMI and waist circumference more than GLP-1 receptor agonists, placebo or insulin, though gastrointestinal side effects were more common.

    ⚠What it shows: Strong pooled evidence: 12 trials with 11,758 people, all assigned at random, and the results pointed the same way against every comparator. The clear trade-off is tolerability, with nausea and other gut side effects markedly more common than placebo.Meta-analysis · Front Public Health

    Full breakdown →Energy balance explained →Calorie Deficit Calculator →Tirzepatide as a novel effective and safe strategy for treating obesity: a systematic review and meta-analysis of randomized controlled trials. Front Public Health 2024
18. Metabolic & GLP-1well supported · human dataAdded 17 August 2026

    GLP-1 drugs show no overall cancer risk across 50 trials, with one thyroid caveat

    Across 50 randomised trials lasting at least a year, GLP-1 receptor agonists were not linked to any overall increase in cancer risk; a signal for higher thyroid cancer risk, and a possible reduction in uterine cancer in obesity trials, both warrant further study.

    ⚠What it shows: Broadly reassuring: results pooled from 50 drug trials that each ran for at least a year found no overall cancer difference. The thyroid signal deserves dedicated study rather than alarm, and several authors report fees from the companies that make these drugs.Meta-analysis · Diabetes Obes Metab

    Full breakdown →GLP-1 explained →Healthy Lifestyle & Life Expectancy →GLP-1 receptor agonists and the risk for cancer: A meta-analysis of randomized controlled trials. Diabetes Obes Metab 2025
19. Women's Healthwell supported · human dataAdded 17 August 2026

    GLP-1 drugs trim weight and insulin resistance in PCOS but leave hormones untouched

    Pooled randomised trials show GLP-1 receptor agonists reduce body weight, BMI, waist measures and insulin resistance in women with PCOS more than metformin or placebo, but hormone levels did not change, HDL cholesterol fell, and nausea, vomiting and dizziness increased.

    ⚠What it shows: Encouraging but incomplete: results pooled from randomised trials in women with PCOS show clear weight and insulin wins, yet the authors themselves call for longer studies. Side effects were common, HDL cholesterol actually fell, and hormone levels did not budge.Meta-analysis · Sci Rep

    Full breakdown →Insulin sensitivity explained →Efficacy and safety of GLP-1 receptor agonists on weight management and metabolic parameters in PCOS women: a meta-analysis of randomized controlled trials. Sci Rep 2025
20. Cardiowell supported · human dataAdded 17 August 2026

    High fitness linked to less than half the death risk of low fitness

    Adults with high cardiorespiratory fitness had a 53% lower risk of dying from any cause than those with low fitness, across pooled evidence from 199 cohort studies and over 20.9 million observations. Every 1-MET higher level of fitness was linked to an 11% to 17% lower risk of all-cause death and an 18% lower risk of heart failure.

    ⚠What it shows: About as convincing as follow-the-people evidence gets: pooled results from 199 studies tracking over 20.9 million observations all point the same way. Because researchers measured fitness and then watched what happened, it shows a powerful link rather than proof that raising your fitness directly causes a longer life.Meta-analysis · Br J Sports Med

    Full breakdown →VO₂max explained →VO2max Calculator →Cardiorespiratory fitness is a strong and consistent predictor of morbidity and mortality among adults: an overview of meta-analyses representing over 20.9 million observations from 199 unique cohort studies. Br J Sports Med 2024
21. Mindwell supported · human dataAdded 17 August 2026

    Exercise matched therapy and antidepressants for easing depression

    Exercise may moderately reduce symptoms of depression in adults, and in head-to-head trials it performed about as well as psychological therapy or antidepressant medication, according to a Cochrane review of 73 randomised trials in at least 4985 people.

    ⚠What it shows: Big on quantity, weaker on quality: results pooled from 73 trials in at least 4985 adults show a moderate benefit, but most trials had design flaws and the effect shrank in the most rigorously run ones. The comparisons with therapy and medication rest on a handful of small trials, so call it a rough draw rather than a verdict.Meta-analysis · Cochrane Database Syst Rev

    Full breakdown →Exercise for depression. Cochrane Database Syst Rev 2026
22. Women's Healthwell supported · human dataAdded 17 August 2026

    Less frequent lifting won for postmenopausal bone density

    Resistance training produced small to moderate gains in bone mineral density at the lumbar spine, femoral neck and total hip in postmenopausal women, across 17 controlled trials. Unexpectedly, programmes with fewer than 2 sessions a week produced bigger gains at the spine and hip than more frequent training, and free weights outperformed machines at the hip.

    ⚠What it shows: Solid for the headline benefit, shaky for the training advice: results pooled from 17 trials show real but modest bone gains in postmenopausal women. The frequency and free-weight findings come from slicing the data into subgroups, and the authors themselves say those slices cannot support firm recommendations.Meta-analysis · Osteoporos Int

    Full breakdown →Strength explained →Training Volume Calculator →Effects of dynamic resistance exercise on bone mineral density in postmenopausal women: a systematic review and meta-analysis with special emphasis on exercise parameters. Osteoporos Int 2020
23. Tech & Wearableswell supported · human dataAdded 17 August 2026

    Blood pressure apps barely work without tailored advice

    Smartphone apps for self-monitoring blood pressure behaviours lowered systolic blood pressure by an average of just 1.64 mmHg across 15 randomised trials in 7415 people treated for hypertension. Apps that added tailored advice achieved a 2.92 mmHg drop, against 0.72 mmHg without it.

    ⚠What it shows: Believable but modest: results pooled from 15 trials where people were assigned at random, covering 7415 people on blood pressure treatment. The average drop is small, and the bigger effect from tailored advice comes from comparing groups of studies with each other rather than from a direct head-to-head test.Meta-analysis · JMIR Mhealth Uhealth

    Full breakdown →Blood pressure explained →Heart Age Calculator →The Association Between Smartphone App-Based Self-monitoring of Hypertension-Related Behaviors and Reductions in High Blood Pressure: Systematic Review and Meta-analysis. JMIR Mhealth Uhealth 2022
24. Trainingwell supported · human dataAdded 17 August 2026

    Women build muscle at the same relative rate as men

    Pooled data from 29 resistance training studies shows men and women gain muscle at similar relative rates when following the same programme. Absolute size gains slightly favoured men, mainly in the upper body, and training experience did not change the pattern.

    ⚠What it shows: About as solid as this question gets for now: results pooled from 29 studies of healthy adults aged 18 to 45 doing identical programmes. Most participants were not highly trained, so whether the pattern holds in seasoned lifters is still an open question.Meta-analysis · PeerJ

    Full breakdown →Hypertrophy explained →Sex differences in absolute and relative changes in muscle size following resistance training in healthy adults: a systematic review with Bayesian meta-analysis. PeerJ 2025

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