Nutrition

1. Nutritionwell supported · human dataAdded 13 August 2026

   Keto did not blunt lifters' one-rep max strength

   Pooled trial data in resistance-trained men and women found a ketogenic diet did not significantly change one-rep max squat (106 participants) or bench press (119 participants) compared with other diets. The reviewers add that a single max lift may not capture performance in longer hypertrophy-style sessions.

   ⚠What it shows: Solid as far as it goes: results pooled from several trials of trained lifters, but only 106 people for squat and 119 for bench, so a small effect either way could be missed. The authors also flag that a one-rep max is a blunt tool for judging how a full training session actually goes.Meta-analysis · Nutrients

   Full breakdown →Strength explained →One-Rep Max Calculator →Effects of the Ketogenic Diet on Strength Performance in Trained Men and Women: A Systematic Review and Meta-Analysis. Nutrients 2024
2. Nutritionwell supported · human dataAdded 13 August 2026

   Not all fibre helps: some supplements raised LDL cholesterol in pooled trials

   Pooled trials in adults with overweight or obesity found fibre supplements modestly improved blood sugar control on average, cutting HbA1c by 0.13% and fasting insulin by 0.82 μIU/mL, but effects split sharply by fibre type: one subgroup saw LDL cholesterol rise by 9.03 mg/dL and another saw systolic blood pressure rise by 3.85 mmHg.

   ⚠What it shows: Trust the headline averages, treat the fibre-type splits with more care: results pooled from 34 trials in 1804 adults with overweight or obesity, but the subgroup comparisons rest on fewer studies and the trials often disagreed with each other. The surprising unfavourable shifts in cholesterol and blood pressure need confirming before anyone rewrites the fibre rulebook.Meta-analysis · Nutr Rev

   Full breakdown →Insulin sensitivity explained →Metabolic Fitness Index →Effects of Supplementation With Different Specificities of Dietary Fiber on Health-Related Indicators in Adults With Overweight or Obesity: A Systematic Review and Meta-analysis of Randomized Controlled Trials. Nutr Rev 2025
3. Nutritionwell supported · human dataAdded 13 August 2026

   Plant protein held its own against animal protein in older adults

   A meta-analysis of 13 randomised trials in adults aged 60 and over found soy protein interventions improved muscle mass over time and matched animal protein and other comparators on body composition, strength and physical function.

   ⚠What it shows: Reassuring rather than dramatic: a sweep of 13 trials in adults over 60, every one using soy at widely varying doses, so it says nothing about pea, rice or blended plant proteins. Effects on strength and function were limited across the board.Meta-analysis · Nutrients

   Full breakdown →Sarcopenia explained →Protein Intake Calculator →Effects of Plant-Based Protein Interventions, with and without an Exercise Component, on Body Composition, Strength and Physical Function in Older Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients 2023
4. Nutritionwell supported · human dataAdded 12 August 2026

   Fibre-fortified foods trimmed weight and cholesterol, and under 15 g a day was enough

   Foods fortified with fibre modestly reduced body weight, fat mass, total and LDL cholesterol, triglycerides, fasting glucose and HbA1c across 31 randomised trials. Solid foods worked better than drinks, and fortification below 15 g per day showed more benefits than higher amounts.

   ⚠What it shows: Strong as nutrition evidence goes: results pooled from 31 trials where people were assigned at random. The fibre types and foods varied widely, and one author works in a major food company's research arm.Meta-analysis · Crit Rev Food Sci Nutr

   Full breakdown →Metabolic syndrome explained →Impact of fiber-fortified food consumption on anthropometric measurements and cardiometabolic outcomes: A systematic review, meta-analyses, and meta-regressions of randomized controlled trials. Crit Rev Food Sci Nutr 2023
5. Nutritionwell supported · human dataAdded 12 August 2026

   Legumes cut cholesterol and blood sugar; the gut benefit went unmeasured in trials

   Providing legumes (average 86 g a day) to 1,938 adults across 24 randomised trials lowered total cholesterol by 0.23 mmol/L, LDL cholesterol by 0.16 mmol/L and fasting glucose by 0.18 mmol/L. Not one eligible trial measured gut microbiome outcomes.

   ⚠What it shows: Worth taking seriously: moderate-certainty results pooled from 24 trials in 1,938 adults, some with existing conditions. The improvements were modest, and no trial was long enough or designed to test the gut microbiome effects legumes are famous for.Meta-analysis · Eur J Nutr

   Full breakdown →Metabolic syndrome explained →Heart Age Calculator →Legume intakes on cardiometabolic profile and gut microbiome function: systematic review and meta-analyses of randomised controlled trials. Eur J Nutr 2024
6. Nutritionwell supported · human dataAdded 12 August 2026

   Fibre lowers blood pressure, but only psyllium moved the needle on its own

   Viscous soluble fibre lowered systolic blood pressure by 1.59 mmHg and diastolic by 0.39 mmHg at a median dose of 8.7 g per day in pooled trials. Of five fibre types tested, only psyllium significantly reduced systolic pressure on its own, by 2.39 mmHg.

   ⚠What it shows: A real but small effect: results pooled from 22 trials in 1,430 people over a median of seven weeks. The studies disagreed with each other considerably, so the exact size of the drop is uncertain.Meta-analysis · Nutr Metab Cardiovasc Dis

   Full breakdown →Fibre explained →Heart Age Calculator →The effect of viscous soluble fiber on blood pressure: A systematic review and meta-analysis of randomized controlled trials. Nutr Metab Cardiovasc Dis 2018
7. Nutritionwell supported · human dataAdded 12 August 2026

   Post-workout protein builds muscle, night-time protein builds strength

   A network meta-analysis of 116 trials in 4,711 adults doing resistance training found protein taken after exercise was most effective for gaining muscle mass, protein at night was most effective for strength, and milk proteins were among the best types; no timing or type improved physical performance tests.

   ⚠What it shows: Solid for muscle and strength, but the rankings come mostly from indirect comparisons because trials rarely pitted one timing against another directly. It pools 116 trials in 4,711 adults doing resistance training, and the evidence was rated moderate certainty.Meta-analysis · Int J Sport Nutr Exerc Metab

   Full breakdown →Muscle protein synthesis explained →Protein Intake Calculator →Effects of Timing and Types of Protein Supplementation on Improving Muscle Mass, Strength, and Physical Performance in Adults Undergoing Resistance Training: A Network Meta-Analysis. Int J Sport Nutr Exerc Metab 2024
8. Nutritionpreliminary · human dataAdded 12 August 2026

   Plant-based eating may dial down a key inflammation marker

   Pooling seven controlled trials in 541 adults, plant-based dietary patterns were associated with C-reactive protein concentrations 1.13 mg/L lower than omnivorous diets, though the trials varied widely and certainty in the result was rated low.

   ⚠What it shows: Promising but not proven: results pooled from just seven trials with 541 people, and the studies disagreed with each other enough that the authors rate the certainty as low. The effect held after stripping out trials that also prescribed exercise, which strengthens the case that diet was doing the work.Meta-analysis · Nutr Metab Cardiovasc Dis

   Full breakdown →Inflammation explained →The effect of plant-based dietary patterns on C-reactive protein: A systematic review and meta-analysis of randomised controlled trials. Nutr Metab Cardiovasc Dis 2026
9. Nutritionwell supported · human dataAdded 11 August 2026

   Ultra-processed food tied to 32 separate health harms

   Greater exposure to ultra-processed food was associated with higher risks across 32 health outcomes in an umbrella review of meta-analyses covering nearly ten million people. Evidence was rated convincing for cardiovascular disease related deaths (risk ratio 1.50, a 50% higher risk), type 2 diabetes, anxiety and common mental disorders.

   ⚠What it shows: As strong as diet-tracking evidence gets without a trial: findings pooled from dozens of studies following nearly ten million people, so the pattern is unlikely to be a fluke. It still cannot prove the food caused the harm, and most of the underlying evidence was rated low or very low quality.Systematic review · BMJ

   Full breakdown →All-cause mortality explained →Healthy Lifestyle & Life Expectancy →Ultra-processed food exposure and adverse health outcomes: umbrella review of epidemiological meta-analyses. BMJ 2024
10. Nutritionwell supported · human dataAdded 10 August 2026

    Oat beta-glucan trims blood pressure by 2.9 mmHg

    Diets rich in beta-glucans, the fibre found in oats and barley, lowered systolic blood pressure by 2.9 mmHg and diastolic by 1.5 mmHg for a median 4 g increase, in pooled trials of healthy adults; higher fibre intake overall produced no significant reduction.

    ⚠What it shows: Solid for the oats finding: results pooled from trials of healthy adults, 18 studies in the final numbers, all lasting at least six weeks. Fibre overall showed no clear effect on blood pressure, so the case here is for beta-glucan sources specifically, not fibre in general.Meta-analysis · J Hypertens

    Full breakdown →Fibre explained →Heart Age Calculator →Effects of dietary fibre type on blood pressure: a systematic review and meta-analysis of randomized controlled trials of healthy individuals. J Hypertens 2015
11. 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
12. Nutritionpreliminary · human dataAdded 8 August 2026

    Watermelon may cut blood pressure, and nudge blood sugar up

    A meta-analysis of 9 randomised controlled trials found watermelon consumption significantly lowered systolic blood pressure, total cholesterol and LDL cholesterol, but also significantly raised fasting blood sugar.

    ⚠What it shows: Meta-analysis of only 9 small RCTs; the authors describe the blood-pressure result as promising but explicitly call for longer, larger trials and urge caution on every outcome beyond blood pressure.Meta-analysis · Diabetes Res Clin Pract

    Full breakdown →Metabolic syndrome explained →Heart Age Calculator →Watermelon consumption decreases risk factors of cardiovascular diseases: A systematic review and meta-analysis of randomized controlled trials. Diabetes Res Clin Pract 2023
13. 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
14. Nutritionwell supported · human dataAdded 6 August 2026

    Whey plus lifting tops the sarcopenia rankings

    In a network meta-analysis of 235 randomised trials covering 20,980 untrained older adults, whey protein plus resistance training ranked as the most effective combination for muscle mass (SMD 1.29) and leg strength (SMD 1.16), while whey plus multicomponent training ranked highest for mobility tasks.

    ⚠What it shows: Network meta-analysis of 235 RCTs in untrained older adults, so most rankings rest on indirect comparisons; certainty was moderate for muscle mass and leg strength, effects were moderated by participant condition and protein dose, and findings may not transfer to already-trained people.Meta-analysis · Nutrients

    Full breakdown →Sarcopenia explained →Protein Intake Calculator →Explore the Optimal Treatment Regimen Across Combinations of Variate Protein Sources and Exercise Modalities and Its Associated Factors in Older Adults: A Network Meta-Analysis and Meta-Regression of Randomized Controlled Trials. Nutrients 2026
15. Nutritionwell supported · human dataAdded 6 August 2026

    Berries barely moved metabolic syndrome markers

    A meta-analysis of 14 randomised trials (327 intervention and 284 control participants with metabolic syndrome) found berry consumption raised HDL cholesterol by 1.771 mg/dL and left almost everything else unchanged: LDL-C, total cholesterol, triglycerides, leptin, BMI, waist circumference, blood pressure, TNF-α, IL-6, CRP, adiponectin, HbA1c, HOMA-IR, glucose and insulin were all unaffected overall.

    ⚠What it shows: Pooled data from 14 small trials in people with metabolic syndrome, using different berries, doses and durations; the HDL rise is tiny and of unclear clinical meaning, and the longer-duration and larger-study signals come from subgroup analyses that are exploratory.Meta-analysis · Int J Food Sci Nutr

    Full breakdown →Metabolic syndrome explained →Metabolic Fitness Index →Effects of berry consumption on cardiometabolic risk factors in patients with metabolic syndrome: a systematic review and meta-analysis of randomised controlled trials. Int J Food Sci Nutr 2025
16. Nutritionpreliminary · human dataAdded 6 August 2026

    Protein alone won't shift body fat in menopause

    A systematic review of 15 randomised trials in 1161 pre- and postmenopausal women found animal proteins such as whey, meat and milk cut body fat more consistently than soy over 8-16 weeks, but mainly when combined with calorie restriction and exercise, and benefits of raising protein alone could not be confirmed.

    ⚠What it shows: Systematic review of 15 RCTs (1161 women), but effects were strongly confounded by co-interventions like energy restriction and exercise, and results across trials were heterogeneous.Systematic review · FASEB J

    Full breakdown →Whey protein guide →Protein Intake Calculator →Dietary Intake of Animal and Plant-Based Protein on Adiposity Measurements and Body Composition in Pre- and Postmenopausal Women: A Systematic Review of Randomized Clinical Trials. FASEB J 2026
17. Nutritionwell supported · human dataAdded 6 August 2026

    Diet-plus-exercise works across the whole BMI range

    In a meta-analysis of 22 diet-and-exercise interventions, overweight participants lost 1.1 kg less over a year than those with class-I obesity and 1.5 kg less than those with class-II obesity, but percentage weight change did not differ significantly across BMI classes.

    ⚠What it shows: Meta-analysis of 22 interventions restricted to healthy Caucasian adults with BMI 25-40; absolute between-class differences were small (1.1-1.5 kg) and findings may not generalise to other ethnic groups or higher BMIs.Meta-analysis · Int J Behav Med

    Full breakdown →Energy balance explained →Calorie Deficit Calculator →Differences in weight loss across different BMI classes: a meta-analysis of the effects of interventions with diet and exercise. Int J Behav Med 2014
18. Nutritionpreliminary · human dataAdded 6 August 2026

    Milk protein beat whey for older lifters' lean mass

    In a meta-analysis of randomised trials in resistance-training adults with a mean age of at least 60 years, 10-15 g of milk protein was sufficient to augment gains in lean body mass, while four out of five studies of whey protein at the same or higher doses showed a negative effect versus control supplementation (-0.49 kg, 95% CI -0.69 to -0.29). Improvements in muscle strength appeared only at protein doses of 22 g or more.

    ⚠What it shows: Twenty studies were reviewed and 17 pooled, all in resistance-training older adults with a mean age of at least 60; the striking whey result rests on just five studies, the review is a between-study comparison rather than a head-to-head trial, and the authors note that adequate daily protein intake dilutes any supplement effect.Meta-analysis · Nutrients

    Full breakdown →Whey protein guide →Protein Intake Calculator →Effects of Milk Protein in Resistance Training-Induced Lean Mass Gains for Older Adults Aged ≥ 60 y: A Systematic Review and Meta-Analysis. Nutrients 2021
19. Nutritionpreliminary · human dataAdded 6 August 2026

    One avocado a day cut harmful LDL particle counts

    In a 26-week randomised trial of 786 adults with abdominal obesity, adding one avocado a day reduced total LDL particle concentration by 49.1 nmol/L versus a habitual diet, with no change in LDL particle size, other lipoprotein particles or apolipoproteins A or B.

    ⚠What it shows: Ancillary analysis of one RCT, n=786 adults with abdominal obesity; lipoprotein particles were exploratory outcomes, and ApoB and every other particle measure did not change: this is a shift in one marker, not a demonstrated reduction in heart disease.Study · J Clin Lipidol

    Full breakdown →ApoB explained →Heart Age Calculator →Effect of incorporating 1 avocado per day on lipoprotein particle concentrations compared to habitual intake in adults with abdominal obesity: An ancillary study of the Habitual Diet and Avocado Trial, a randomized controlled trial. J Clin Lipidol 2026
20. Nutritionwell supported · human dataAdded 6 August 2026

    Anthocyanins linked to 26% lower CVD incidence

    Pooling 18 cohorts and 65 randomised trials in healthy people, the highest habitual anthocyanin intakes were associated with 26% lower cardiovascular disease incidence, 18% lower myocardial infarction and 11% lower type 2 diabetes risk, while trials using at least 50 mg/d improved flow-mediated dilation (net change 1.41% with chronic intake) and left lipids, blood pressure and glucose unchanged.

    ⚠What it shows: Systematic review and meta-analysis: the risk reductions come from prospective cohorts, which show association not causation and can be confounded by wider diet quality, while the trial evidence covers surrogate biomarkers such as vessel function rather than heart attacks or deaths. The review was part-funded by a blueberry industry council, and one author advises its grant committee, though the funder is stated to have had no role in study selection or analysis.Meta-analysis · Am J Clin Nutr

    Full breakdown →Metabolic syndrome explained →Heart Age Calculator →Dietary intakes of anthocyanins and cardiometabolic health: a systematic review and meta-analysis of randomized trials and prospective cohort studies in healthy participants. Am J Clin Nutr 2026
21. Nutritionwell supported · human dataAdded 6 August 2026

    Low-carb traded lower triglycerides for higher LDL

    In a meta-analysis of randomised trials in people with overweight or obesity, hypocaloric low-carbohydrate diets were no better than low-fat diets for blood pressure, CRP, HDL, total cholesterol or body composition; they lowered triglycerides by 19.94 mg/dL but raised LDL by 20.00 mg/dL. Only very-low-carbohydrate versions significantly reduced flow-mediated dilation, a measure of blood-vessel function, by 2.12%.

    ⚠What it shows: Systematic review and meta-analysis of randomised trials in adults with overweight or obesity, with only 10 studies (n = 475) reporting the vascular outcome; diets were calorie-restricted, trial lengths and carbohydrate definitions varied, and the overall low-carb effect on vessel function was not statistically significant.Meta-analysis · Eur J Clin Nutr

    Full breakdown →ApoB explained →Macro Calculator →Hypocaloric low-carbohydrate versus low-fat diets on flow-mediated dilation, blood pressure, cardiovascular biomarkers, and body composition in individuals with overweight or obesity: a systematic review and meta-analysis of randomized clinical trials. Eur J Clin Nutr 2025
22. Nutritionwell supported · human dataAdded 6 August 2026

    Higher fibre intake tracks with 22% lower cancer risk

    An umbrella review pooling meta-analyses of observational studies linked higher dietary fibre intake to a 22% lower cancer risk and 17% lower cancer mortality, with the strongest inverse association for digestive tract cancers and a smaller one for breast cancer. Observational data cannot establish cause.

    ⚠What it shows: Umbrella review and meta-meta-analysis of 25 papers and 28 reports, all built on observational epidemiology: people who eat more fibre differ in many other ways, and no randomised trial evidence is included, so causation is not established.Meta-analysis · Crit Rev Food Sci Nutr

    Full breakdown →Fibre explained →High and low dietary fiber consumption and cancer risk: a comprehensive umbrella review with meta-meta-analysis involving meta-analyses of observational epidemiological studies. Crit Rev Food Sci Nutr 2025
23. Nutritionpreliminary · human dataAdded 6 August 2026

    16:8 bulk built the same muscle with less fat

    In a 12-week randomised trial, 23 resistance-trained adults bulking on a 16:8 time-restricted eating schedule gained similar fat-free mass, muscle mass and 1RM strength to controls, but significantly less body weight and fat mass. The time-restricted group ate fewer calories, protein and carbohydrate than prescribed, so the smaller fat gain reflects intake falling short of the target surplus rather than meal timing itself.

    ⚠What it shows: Small 12-week RCT in 23 healthy resistance-trained individuals, with body composition measured by single-frequency bioelectrical impedance; the eating-window group failed to hit the prescribed energy surplus, so the fat-mass difference is confounded by lower intake.Study · J Nutr

    Full breakdown →Muscle protein synthesis explained →Protein Intake Calculator →Time-Restricted Eating during a Bulking Phase Is Associated with Reduced Fat Accumulation, while Muscle and Strength Gains Are Maintained: A 12-Wk Randomized Controlled Trial. J Nutr 2026
24. Nutritionpreliminary · human dataAdded 6 August 2026

    Adding a fasting window didn't cut hunger further

    In a 24-week randomised trial of 120 overweight or obese adults with type 2 diabetes, calorie-carbohydrate restriction with or without time-restricted eating significantly reduced hunger and increased satiety compared with control, with no significant difference between the two intervention groups. Binge eating scale scores and objective binge episodes did not differ significantly between any of the groups at any time point.

    ⚠What it shows: One 24-week randomised trial with 120 adults with type 2 diabetes, 40 per group; appetite was rated on subjective scales, participants were not selected for high baseline binge eating scores, and binge outcomes did not move.Study · Appetite

    Full breakdown →Energy balance explained →Calorie Deficit Calculator →Effects of intensive lifestyle interventions with calorie-carbohydrate-restricted diet versus time-restricted eating on appetite and binge eating in type 2 diabetes: A randomized controlled trial. Appetite 2026

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