For how we live.
A network meta-analysis of 163 trials found EPA, vitamin D and a St John's wort extract beat placebo by margins so large the researchers treat them as a warning about the evidence, not a green light.
A meta-analysis of more than 155,000 children finds mortality is elevated even at oxygen saturations of 90–94%, above the threshold at which WHO advises hospital oxygen.
Cochrane reviews rate anti-inflammatory painkillers a very effective treatment for menstrual cramps, roughly doubling the odds of good pain relief. Exercise helps too, but on lower-quality evidence.
A network meta-analysis of 53 studies and more than 7 million admissions finds machine learning out-discriminates traditional sepsis scores — and would raise roughly two false alarms for every real one.
A meta-analysis of 14 studies and 7,465 men found little for the conventional semen parameters, and something more consistent for sperm DNA fragmentation.
A Cochrane review found women doing pelvic floor muscle training were eight times more likely to report their stress incontinence cured than untreated women — with the strongest evidence for that one condition.
The gap between those two numbers is the whole argument. An individual-patient meta-analysis of 20,827 people found real effects on both comparisons, and found that the choice of sham changed the answer.
A review screening 14,125 articles found evidence neither for nor against morning or evening training — only that testing and training at the same hour helps. Evening sessions may cost some sleep continuity.
A Cochrane review of 50 trials found cranberry products lower UTI risk in women with recurrent infections and in children, but no benefit in the elderly, in pregnancy, or in bladder-emptying problems.
A meta-analysis of 51 studies found no effect on race time or time to exhaustion. The 2026 review of post-exercise compression for soreness rated its own evidence very low certainty.
A 2026 meta-analysis of 86 randomised trials found body mass, waist circumference and maximal oxygen uptake still better than baseline more than six months after training stopped. Not everything held.
A meta-regression of 23 hypertrophy studies found total intake the strongest predictor and no timing effect after adjustment. A later network meta-analysis of 116 trials still favours post-exercise, narrowly.
A 2026 meta-analysis of 19 trials found training at maximal fat-oxidation intensity cut body weight by 3.66 kg. Head-to-head trials against interval training find no consistent winner on body fat.
In a meta-analysis of 25 randomised trials and 26,610 participants, stretching produced no reduction in sports injuries. Strength training cut them to under a third — on a much smaller evidence base.
A 223-study meta-regression reports sperm concentration falling 51.6% since 1973. Two published critiques argue the method cannot support that reading. Both sides are peer-reviewed.
A review of 110 studies found that 52% of trialled self-guided apps were publicly available — and that evidence quality had no bearing on which ones made it to an app store.
A meta-analysis of six studies found a moderate effect on sleep duration and a small one on depressive symptoms — with high heterogeneity on both.
The meta-analysis behind ketamine's widening off-label use for suicidal crisis quantifies what 1,166 patients across two decades of trials actually showed — and where the evidence runs out.
Pooling 11 cohort studies, researchers found a consistent cardiovascular signal in Asian and North American cohorts. European cohorts showed no elevated risk at all, a geographic split the analysis can't explain.
A meta-analysis of fully automated programmes found a large effect on insomnia severity. A review of 68 studies found the field has barely measured whether recipients find them acceptable.
A review pooling 23 studies found risk concentrated among people with bipolar I disorder, family history, or unsupervised use. About 4% later transitioned to bipolar disorder.
A network meta-analysis compared the ways athletes split training across intensity zones. Every credible interval crossed zero — and the model ranked first for aerobic capacity was not the popular one.
Pooling decades of research, the combined estrogen-progestin regimen showed a 44% higher breast cancer risk. Estrogen-only therapy showed none in observational studies — and trials suggested it lowered risk.
Pooling 94 cohort studies, grip strength tracked with later dementia, depression and disability. The authors rate their own confidence in the numbers as limited to moderate.
An Oxford meta-analysis of 37 studies puts average regain at 0.4 kg a month across all weight-management drugs, and 0.8 kg a month for semaglutide and tirzepatide. Almost none of the newer-drug data runs past a year.
Pooling ten studies, researchers found menopause hormone therapy neither raised nor lowered dementia risk. The certainty of that evidence ranged from moderate to very low.
An individual-patient meta-analysis of 17,801 patients found a hazard ratio of 0.97 for death, reinfarction or heart failure — a result precise enough to make the question look settled.
A meta-analysis of 22 crossover trials with overnight polysomnography found consistent losses in total sleep time and efficiency. The age and dose subgroup differences everyone wants were not statistically significant.
Pooling individual data from 23,340 people in four trials, empagliflozin cut kidney failure by 34% and slowed eGFR decline by 64% — regardless of how big an initial creatinine rise was expected.
Pooling 31 studies of 556 patients, cortical 5-HT2A binding was lower in unmedicated depression than in controls. The post-mortem studies mostly found nothing, and the tracers used shape the result.
A meta-analysis of pedometer, tracker and smartwatch interventions lasting 12 to 48 weeks found no significant change in systolic or diastolic pressure — nor in weight, glucose or HbA1c.
Collagen, flavanols and polyphenols beat their comparators on skin elasticity and sun tolerance. The pooled estimates carry heterogeneity of 95% to 98%, and some comparators were low doses of the same ingredient.