Every study, searchable

Search the studies

Nutritionwell supported · human dataAdded 8 August 2026
Steeper calorie cuts cost more muscle: exercise protects it
In a systematic review of weight loss exceeding 10 kg, harsher caloric restriction was associated with a larger share of the lost weight coming from fat-free mass, while adding exercise reduced the proportion of lean tissue lost.
What it shows: Systematic review pooling 26 diet/behavioural cohorts and 29 bariatric-surgery cohorts, mostly observational; the exercise finding rests on just three RCTs; applies to large weight losses of more than 10 kg.Systematic review · Int J Obes (Lond)
Full breakdown →Calorie deficit explained Calorie Deficit Calculator Changes in fat-free mass during significant weight loss: a systematic review. Int J Obes (Lond) 2007
Supplementswell supported · human dataAdded 8 August 2026
Creatine does nothing for endurance in trained athletes
Creatine monohydrate did not improve endurance performance in trained people across 13 placebo-controlled trials, with a trivial, non-significant pooled effect of -0.07.
What it shows: Meta-analysis of 13 placebo-controlled trials in trained populations only; endurance tests varied between studies; the finding does not contradict creatine's established benefit for short, high-intensity exercise.Meta-analysis · Sports Med
Full breakdown →Creatine monohydrate guide Creatine Calculator Effects of Creatine Monohydrate on Endurance Performance in a Trained Population: A Systematic Review and Meta-analysis. Sports Med 2023
Environmentwell supported · human dataAdded 8 August 2026
Cold waves carry a 40% higher death risk for people with diabetes
Pooled data from eight studies link cold-wave exposure to a 40% increase in diabetes-related mortality risk (relative risk 1.40); the rise in diabetes-related illness was smaller and not statistically significant.
What it shows: Meta-analysis of eight observational studies; the morbidity estimate was not statistically significant (its confidence interval crossed 1) and risk varied across studies, suggesting environmental and healthcare disparities between settings.Meta-analysis · Front Public Health
Full breakdown →Impact of cold waves on diabetes-related morbidity and mortality: a meta-analysis. Front Public Health 2025
Trainingpreliminary · human dataAdded 8 August 2026
Strength training helps sarcopenic obesity even when body composition won't budge
In older adults with sarcopenic obesity, high-speed circuit resistance training significantly improved muscle strength and physical function, even though neither exercise nor an extra 15 g of daily protein changed body composition.
What it shows: Systematic review that found only two eligible trials (61 participants in total, mean age ≥65); the evidence base is very thin and body composition did not change significantly in either study.Systematic review · Nutr Res
Full breakdown →Sarcopenia explained Body Fat Calculator Effectiveness of nutritional and exercise interventions to improve body composition and muscle strength or function in sarcopenic obese older adults: A systematic review. Nutr Res 2017
Supplementspreliminary · human dataAdded 8 August 2026
Sesame may boost athletes' antioxidant defences: exercise does the rest
In semiprofessional athletes doing aerobic training, four small trials suggest sesame supplementation boosted antioxidant defences and lowered the oxidative-stress marker malondialdehyde; reductions in inflammatory cytokines appeared to come mainly from the exercise itself.
What it shows: Systematic review of just four RCTs (140 semiprofessional athletes, 4-10 weeks); outcomes were blood biomarkers only, with no direct performance or recovery measures, so replication and functional endpoints are needed.Systematic review · Nutr Health
Full breakdown →Antioxidant explained Recovery Readiness Index The emerging role of sesame supplementation with aerobic exercise in athlete recovery and immunomodulation: A systematic review of human trials. Nutr Health 2026
Supplementswell supported · human dataAdded 8 August 2026
Tart cherry trims one inflammation marker, and leaves the others alone
Outside of exercise settings, tart cherry lowered the inflammation marker C-reactive protein by an average of 0.55 mg/L across ten randomised trials, but had no significant effect on IL-6 or TNF-α.
What it shows: Meta-analysis of 10 non-exercise RCTs; the CRP reduction was modest, IL-6 showed no significant change, and TNF-α was assessed in only three studies, also with no significant effect.Meta-analysis · Complement Ther Med
Full breakdown →Tart cherry guide The beneficial effect of tart cherry on plasma levels of inflammatory mediators (not recovery after exercise): A systematic review and meta-analysis on randomized clinical trials. Complement Ther Med 2022
Supplementswell supported · human dataAdded 8 August 2026
Curcumin plus black-pepper extract shifts blood fats: except LDL
Across 16 randomised trials in 1038 adults, curcuminoids taken with piperine significantly lowered triglycerides and total cholesterol and modestly raised HDL cholesterol; LDL cholesterol did not fall significantly.
What it shows: Meta-analysis of 16 RCTs (1038 adults); effects were modest, the LDL-C change was non-significant, and benefits were most pronounced with longer supplementation and in people with dyslipidaemia, metabolic disorders or overweight.Meta-analysis · Lipids
Full breakdown →Curcumin guide Heart Age Calculator Effects of Curcuminoids Plus Piperine Co-Supplementation on Serum Lipid Profile in Adults: A Systematic Review and Meta-Analysis of RCTs. Lipids 2026
Supplementswell supported · human dataAdded 8 August 2026
Supplement users were 2.74 times more likely to report doping
Across 26 cross-sectional studies of 13,296 athletes, doping was 2.74 times more prevalent among dietary supplement users (14.7%) than non-users (6.7%), and supplement users also reported stronger doping intentions and attitudes.
What it shows: All 26 included studies were cross-sectional, so the link is an association and cannot show supplement use causes doping; doping was self-reported and measurement of supplement use was inconsistent across studies.Meta-analysis · Int J Drug Policy
Full breakdown →Are dietary supplement users more likely to dope than non-users?: A systematic review and meta-analysis. Int J Drug Policy 2023
Bones & Jointswell supported · human dataAdded 8 August 2026
For chronic back pain, only movement held up long term
A systematic review of 85 studies on chronic non-specific low back pain found that only movement therapy showed evidence of long-term effectiveness. Bed rest, TENS, massage, spine supports, back schools and antidepressants showed no evident effectiveness, while injections, NSAIDs, heat and opioids helped only in the short term.
What it shows: Review of German and English literature from 2004 to 2015; therapies were assessed as broad categories, 'long term' meant beyond 6 weeks, and the evidence base is now around a decade old.Meta-analysis · Orthopade
Full breakdown →Back Pain [Conservative treatment of nonspecific, chronic low back pain : Evidence of the efficacy - a systematic literature review]. Orthopade 2016
Supplementswell supported · human dataAdded 8 August 2026
Black seed supplements cooled inflammation markers in metabolic syndrome
A meta-analysis of 16 randomised controlled trials in 1033 people with metabolic syndrome and related disorders found that Nigella sativa (black seed) supplementation significantly reduced inflammatory markers, CRP, TNF-α and IL-6, and improved oxidative stress markers versus placebo.
What it shows: Meta-analysis of 16 RCTs (n=1033) in patients with metabolic syndrome and related disorders; outcomes are blood biomarkers, not disease events, and the authors themselves conclude only that intake 'could be associated' with improvement.Meta-analysis · Curr Pharm Biotechnol
Full breakdown →Metabolic syndrome explained Effect of Nigella sativa Intake on Oxidative Stress and Inflammation in Patients with Metabolic Syndrome and Related Disorders: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Curr Pharm Biotechnol 2024
Sleeppreliminary · human dataAdded 8 August 2026
Clearing the sinuses tracked with quieter, steadier breathing at night
Across 15 studies, treating rhinosinusitis medically or surgically was frequently followed by reductions in the apnoea-hypopnoea index and improvements in endoscopic findings, sleep quality and daytime sleepiness, although subjective nasal symptom outcomes varied between studies.
What it shows: Systematic review of 15 mostly before-and-after studies with treatments ranging from sinus surgery to biologics; heterogeneity was too great for any pooled estimate, so no effect size exists and uncontrolled designs cannot establish cause.Systematic review · Medicina (Kaunas)
Full breakdown →The Impact of Rhinosinusitis and Its Treatment on Sleep-Disordered Breathing: A Systematic Review. Medicina (Kaunas) 2026
Longevitywell supported · human dataAdded 8 August 2026
Walking-based rehab gets older adults moving again after illness
In a meta-analysis of 29 randomised trials with 7,076 older adults, community rehabilitation built around outdoor walking plus behaviour-change support increased physical activity, endurance and outdoor mobility in those recovering from illness or injury, with effects preserved at follow-up where reported. Falls-related self-efficacy did not improve.
What it shows: Meta-analysis of 29 RCTs (7,076 participants), but 66% of trials were at high risk of bias in at least one domain; the clearest effects came from small subsets of trials (two to seven per outcome) and applied to older adults recovering from illness or injury, not to already-well community-dwellers.Meta-analysis · Age Ageing
Full breakdown →Healthspan explained The effectiveness of rehabilitation interventions including outdoor mobility on older adults' physical activity, endurance, outdoor mobility and falls-related self-efficacy: systematic review and meta-analysis. Age Ageing 2022
Supplementspreliminary · human dataAdded 8 August 2026
Early review found protein supplement evidence too thin to recommend
A systematic review of nine randomised trials in healthy people found lean-mass gains of 0.8 to 1.9 kg with protein supplementation during resistance training, but the longest trial lasted only 12 weeks. The authors concluded the evidence did not support recommending protein supplements for healthy individuals.
What it shows: Systematic review of only nine RCTs in healthy subjects, searched up to April 2009; only three studies reached level 3 evidence and the longest intervention was 12 weeks, so the conclusion reflects a thin, dated trial base rather than a definitive verdict.Systematic review · Arch Latinoam Nutr
Full breakdown →Whey protein guide Protein Intake Calculator [Effectivity in the use of protein supplements in resistance training: systematic review]. Arch Latinoam Nutr 2010
Mindpreliminary · human dataAdded 8 August 2026
Slow breathing cut chronic pain by up to 37% in the strongest trials
In a systematic review of ten randomised trials in adults with chronic pain conditions such as neck pain, low back pain, fibromyalgia and tension-type headache, the two trials judged at low risk of bias, both testing 15 minutes of daily slow diaphragmatic breathing, showed clinically relevant pain reductions of up to 37%. The reviewers stress that the overall evidence remains sparse.
What it shows: Systematic review of 10 RCTs (638 participants total) with trial quality ranging from high to critically low; heterogeneity prevented pooling of results, and the strongest finding rests on just two low-bias trials: the authors themselves call the evidence sparse.Systematic review · Scand J Pain
Full breakdown →Breathwork for Recovery and Stress Breathing therapy as a supplement to opioid management for complex chronic non-cancer pain conditions - a systematic review. Scand J Pain 2026
Longevitypreliminary · human dataAdded 8 August 2026
Exercise did not lengthen telomeres in women overall
Across 17 studies of women, physical activity overall showed no significant relationship with telomere length, a marker of cellular ageing. A possible positive relationship appeared only for combined aerobic-plus-strength programmes and high-intensity interval training, and only in early and later adulthood rather than middle adulthood.
What it shows: Systematic review with narrative synthesis of 17 studies (2008-2022) in women; most observational and reliant on self-reported activity, with wide variation in exercise type, intensity, duration and frequency, so no firm conclusions could be drawn and race or ethnicity analyses were inconclusive.Systematic review · Mech Ageing Dev
Full breakdown →Biological age explained Phenotypic Age Calculator The relationship between physical activity and telomere length in women: A systematic review. Mech Ageing Dev 2025
Metabolic & GLP-1well supported · human dataAdded 8 August 2026
Exercise cut fasting insulin across 58 trials in women
Pooling 58 randomised trials in adult women, exercise interventions reduced fasting insulin, insulin resistance (HOMA-IR) and fasting glucose compared with control. IGF-1 rose, with no clear effect on IGFBP-3 or the IGF-1:IGFBP-3 ratio, and the evidence was graded strong only for fasting insulin and insulin resistance.
What it shows: Systematic review and meta-analysis of 58 randomised controlled trials in adult women; no observational or Mendelian randomisation studies qualified, evidence certainty was strong for only two of the outcomes, and effects on C-peptide and HbA1c remain unexamined.Systematic review · Cancer Epidemiol Biomarkers Prev
Full breakdown →Insulin sensitivity explained Metabolic Fitness Index Linking Physical Activity to Breast Cancer Risk via Insulin/Insulin-Like Growth Factor Signaling System, Part 1: The Effect of Physical Activity on the Insulin/Insulin-Like Growth Factor Signaling System. Cancer Epidemiol Biomarkers Prev 2022
Bones & Jointspreliminary · human dataAdded 8 August 2026
Cognitive functional therapy may not beat manual therapy for back pain
Pooling five randomised trials (n = 507), cognitive functional therapy may be no more effective than manual therapy plus core exercises for reducing pain and disability in chronic low back pain, with the pooled estimates so imprecise that the certainty of evidence was rated very low. No adverse events were reported.
What it shows: Systematic review and meta-analysis of 15 identified trials, of which only 5 provided data (n = 507; 262 cognitive functional therapy, 245 control); all studies were judged at high risk of bias, confidence intervals were extremely wide, and 9 trials were still ongoing.Meta-analysis · J Orthop Sports Phys Ther
Full breakdown →Back Pain Effectiveness of Cognitive Functional Therapy for Reducing Pain and Disability in Chronic Low Back Pain: A Systematic Review and Meta-analysis. J Orthop Sports Phys Ther 2023
Metabolic & GLP-1well supported · human dataAdded 8 August 2026
GLP-1 in a pill: big weight loss, familiar gut toll
A meta-analysis of ten randomised trials found oral small-molecule GLP-1 receptor agonists significantly reduced body weight, waist circumference and HbA1c in adults with type 2 diabetes or obesity, and made a weight loss of 15% or more 10.61 times more likely. Gastrointestinal side effects rose sharply, but serious adverse events did not increase.
What it shows: Meta-analysis of ten RCTs in adults with type 2 diabetes or obesity; the abstract does not report total participant numbers or trial durations, and gastrointestinal side effects were substantially more common on the drugs.Meta-analysis · Front Endocrinol (Lausanne)
Full breakdown →Insulin sensitivity explained Calorie Deficit Calculator Investigation into the efficacy and safety profile of oral small-molecule GLP-1 receptor agonists in type 2 diabetes and obesity: a systematic review and meta-analysis. Front Endocrinol (Lausanne) 2026
Metabolic & GLP-1well supported · human dataAdded 8 August 2026
Tirzepatide improves how physically capable people feel
A meta-analysis of six randomised trials in 4531 adults with overweight or obesity found once-weekly tirzepatide (10 or 15 mg) improved patient-reported physical function versus placebo, by 2.26 points on the SF-36 physical function domain and 10.10 points on the IWQOL-Lite-CT physical function subscale, though between-study heterogeneity was extreme.
What it shows: Meta-analysis of six RCTs (4531 participants, 2802 on tirzepatide); outcomes were self-reported questionnaires, heterogeneity was extreme (I2 = 99.8%) and GRADE certainty only moderate due to risk of bias and inconsistency.Meta-analysis · Diabetes Obes Metab
Full breakdown →Healthspan explained Tirzepatide on physical function in adults with overweight or obesity: A systematic review and meta-analysis. Diabetes Obes Metab 2026
Metabolic & GLP-1well supported · human dataAdded 8 August 2026
Weight loss on tirzepatide roughly doubles without diabetes
In a meta-analysis of ten randomised trials, once-weekly tirzepatide reduced body weight by an average of 18.11 kg versus placebo in adults without diabetes, but by 9.06 kg in adults with diabetes, with mostly mild-to-moderate side effects in both groups.
What it shows: Meta-analysis of placebo-controlled RCTs of at least 26 weeks: five trials (n=2,174) in adults with diabetes and five (n=4,467) without. The abstract does not explain why the effect differs by diabetes status.Meta-analysis · Int J Obes (Lond)
Full breakdown →Energy balance explained Calorie Deficit Calculator Effects of tirzepatide on weight management in patients with and without diabetes: a systematic review and meta-analysis. Int J Obes (Lond) 2025
Metabolic & GLP-1well supported · human dataAdded 8 August 2026
Semaglutide cuts heart-rhythm and cardiovascular risks in type 2 diabetes
A meta-analysis of 30 randomised trials in 32490 people with type 2 diabetes found semaglutide reduced atrial fibrillation, complete heart block, death from cardiovascular causes and revascularisation compared with controls, with longer treatment showing greater benefits for heart-rhythm outcomes.
What it shows: Meta-analysis of 30 RCTs in people with type 2 diabetes only; confidence intervals for atrial fibrillation and cardiovascular death approach the line of no effect, and the findings may not extend to people without diabetes.Meta-analysis · Front Endocrinol (Lausanne)
Full breakdown →Heart Age Calculator Effect of semaglutide on arrhythmic, major cardiovascular, and microvascular outcomes in patients with type 2 diabetes: a systematic review and meta-analysis. Front Endocrinol (Lausanne) 2025
Hormonespreliminary · human dataAdded 8 August 2026
The post-workout testosterone spike depends on how you measure it
A meta-analysis of 21 studies found salivary testosterone and cortisol generally rise after acute aerobic, resistance and power exercise in men, but the size of the response varied heavily with study design and when baseline samples were taken, and the authors judged the overall evidence weak.
What it shows: Only 2 of the 21 included studies were randomised controlled trials and 18 were uncontrolled; effect sizes differed sharply by design and baseline sampling time, and the authors call for standardised salivary hormone methodology.Meta-analysis · Sports Med
Full breakdown →Cortisol explained Recovery Readiness Index Exercise-induced responses in salivary testosterone, cortisol, and their ratios in men: a meta-analysis. Sports Med 2015
Women's Healthpreliminary · human dataAdded 8 August 2026
Intermittent fasting linked to 4.25 kg weight loss in PCOS
In a meta-analysis of five studies, intermittent fasting reduced body weight by an average of 4.25 kg in women with PCOS, alongside improvements in BMI, insulin resistance, triglycerides, free androgens and inflammation, though total testosterone, cholesterol and waist-to-hip ratio did not change.
What it shows: Meta-analysis of only five studies; the authors themselves describe the evidence as preliminary, and several hormone and lipid outcomes (total testosterone, cholesterol, AMH) showed no significant change.Meta-analysis · Nutrients
Full breakdown →Insulin sensitivity explained Calorie Deficit Calculator Effect of Intermittent Fasting on Anthropometric Measurements, Metabolic Profile, and Hormones in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis. Nutrients 2025
Women's Healthwell supported · human dataAdded 8 August 2026
Oestrogen-only HRT raises womb-lining risk, adding progestogen offsets it
A Cochrane review of 45 randomised trials found oestrogen-only hormone therapy increases the risk of endometrial hyperplasia at all doses in postmenopausal women, while regimens combining low-dose oestrogen continuously with at least 1 mg norethisterone acetate or 1.5 mg medroxyprogesterone acetate carried no greater risk than placebo.
What it shows: 2009 Cochrane review (a later update exists); applies to postmenopausal women with an intact uterus, and small study numbers plus clinical heterogeneity prevented meta-analysis for many outcomes.Meta-analysis · Cochrane Database Syst Rev
Full breakdown →Hyperplasia explained Hormone therapy in postmenopausal women and risk of endometrial hyperplasia. Cochrane Database Syst Rev 2009

Back to the full archive · this week’s studies