Nutrition

1. Nutritionpreliminary · human dataAdded 6 August 2026

   Meal timing didn't beat usual care on liver fat

   In a 12-week multicentre randomised trial, adding early, late or self-selected 8-hour time-restricted eating to Mediterranean diet-based usual care reduced MRI-measured hepatic fat within each group, but none of the timings beat usual care or each other, and liver markers and faecal microbiota showed no between-group differences. Larger liver fat reductions tracked with baseline steatosis and with achieving ≥5% weight loss, which more people managed on time-restricted eating than on usual care (41-44% vs 16%).

   ⚠What it shows: One 12-week randomised trial in adults with overweight or obesity (arms of 49, 49, 52 and 47); the study was not powered for secondary outcomes such as liver markers and microbiota, and follow-up ended at 12 weeks.Study · JHEP Rep

   Full breakdown →Energy balance explained →Calorie Deficit Calculator →Time-restricted eating, liver health, and fecal microbiota in adults with overweight or obesity: a randomized controlled trial. JHEP Rep 2026
2. Nutritionpreliminary · human dataAdded 1 August 2026

   Marathon inflammation faded by 48 hours in runners

   In 31 recreational marathon runners, IL-6 and IL-10 spiked immediately after the race and were back to pre-race levels by 48 h. Habitual intake of the long-chain monounsaturated fat 20:1 was the only dietary fat associated with higher IFN-γ and TNF-α at 48 h.

   ⚠What it shows: Exploratory observational study in just 31 recreational marathon runners (58.1% female, mean age 38.4 years); habitual fat intake came from a food-frequency questionnaire, dozens of fat-cytokine associations were tested, and the authors themselves call for replication in larger cohorts. Association only, and no health outcome was measured.Study · Nutrients

   Full breakdown →Dietary fat explained →Macro Calculator →The Associations Between Habitual Dietary Fat Intake and Inflammatory Markers Among Marathon Runners: An Exploratory Study. Nutrients 2026
3. Nutritionpreliminary · human dataAdded 29 July 2026

   Intra-workout protein added nothing over carbs alone

   Young men taking protein with carbohydrate during their workouts gained no more muscle fibre size, lean mass or strength over 8 weeks than men taking carbohydrate alone with the same calories. The resistance training itself worked well in both groups, raising lean mass, strength, VO2max, fat oxidation and fibre cross-sectional area.

   ⚠What it shows: Small exploratory RCT: just 17 physically active young men (8 vs 9) over 8 weeks, which the authors say cannot exclude modest effects; a null result from an underpowered trial, not proof of no benefit.Study · Nutrients

   Full breakdown →Muscle protein synthesis explained →Protein Intake Calculator →Effect of Intra-Workout Protein-Carbohydrate Co-Ingestion Versus Isocaloric Carbohydrate During Resistance Training on Muscle Fibre Hypertrophy and Oxidative Capacities in Young Men: A Randomized Controlled Trial. Nutrients 2026
4. Nutritionpreliminary · human dataAdded 29 July 2026

   GLP-1 users ate about 271 kcal less at test lunch

   Pooling placebo-controlled trials, people on GLP-1 or dual GIP/GLP-1 receptor agonists ate about 271 kcal less at a standardised ad libitum lunch, a pooled reduction of 1132 kJ with no heterogeneity between trials. The difference between semaglutide and tirzepatide was not statistically significant.

   ⚠What it shows: The primary pooled estimate rests on just four arms from three trials with 209 participants, and measures a single laboratory test meal rather than habitual eating; the authors note real-world dietary intake remains underreported.Review · Diabetes Metab Syndr

   Full breakdown →Energy balance explained →Calorie Deficit Calculator →Nutritional intake changes during GLP-1 receptor agonist therapy: A systematic review and meta-analysis. Diabetes Metab Syndr 2026
5. Nutritionpreliminary · human dataAdded 29 July 2026

   Med diet shifted the metabolism of ageing brains

   In an interim analysis of a 24-week trial in 47 older adults with mild cognitive impairment, a Mediterranean diet raised ketone and TCA-cycle metabolites and lowered branched-chain amino acids, while a low-fat diet did not; several of those metabolite shifts tracked with better cognitive scores.

   ⚠What it shows: Interim metabolomics analysis of a randomised trial in just 47 adults aged 60 and over with mild cognitive impairment, over 24 weeks. The metabolite-cognition links are associations within the trial, not proof that the diet improved cognition, and the sample is far too small to be conclusive.Study · Food Funct

   Full breakdown →BCAAs guide →Metabolic Fitness Index →Enhanced metabolic flexibility links Mediterranean diet with cognition: interim findings from a randomized controlled trial. Food Funct 2026
6. Nutritionwell supported · human dataAdded 29 July 2026

   Protein's muscle payoff stalls past 1.62 g/kg/day

   Across 49 randomised trials with 1863 healthy adults, adding protein supplements to resistance training increased fat-free mass by 0.30 kg and one-rep-max strength by 2.49 kg on average. Once total protein intake passed roughly 1.62 g/kg/day, extra protein added nothing further to fat-free mass gains.

   ⚠What it shows: Meta-analysis of 49 RCTs in healthy adults training for at least six weeks, so the pooled effects are solid but small in absolute terms; the 1.62 g/kg/day ceiling comes from a break-point analysis of group averages, not an individualised threshold, and the senior author discloses dairy-industry grant support.Meta-analysis · Br J Sports Med

   Full breakdown →Muscle protein synthesis explained →Protein Intake Calculator →A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med 2018
7. Nutritionwell supported · human dataAdded 29 July 2026

   More protein means more muscle, but only a little

   A meta-analysis of 74 randomised trials found that eating more protein adds small extra gains in lean mass and lower-body strength for healthy adults doing resistance training. Lean-mass benefits appeared at 1.2-1.59 g of protein per kg per day in adults 65 and over, and at 1.6 g/kg/day or more in younger adults.

   ⚠What it shows: Meta-analysis of 74 RCTs in healthy, non-obese adults; the lean-mass effect was small (SMD 0.22, moderate-level evidence), strength evidence was rated low, and some authors have food-industry ties.Meta-analysis · J Cachexia Sarcopenia Muscle

   Full breakdown →Muscle protein synthesis explained →Protein Intake Calculator →Systematic review and meta-analysis of protein intake to support muscle mass and function in healthy adults. J Cachexia Sarcopenia Muscle 2022
8. Nutritionwell supported · human dataAdded 29 July 2026

   Dieting alone risks muscle loss near retirement age

   A network meta-analysis of 92 trials in adults aged 55-70 with overweight or obesity found that combining calorie restriction with resistance or mixed exercise and high protein intake was the most effective strategy for nearly all body-composition outcomes. Energy restriction alone was less effective and tended to decrease muscle mass.

   ⚠What it shows: Network meta-analysis of RCTs: 92 studies included, 66 of them (4,957 participants) usable for pooling; interventions lasted only 8 weeks to 6 months, and network comparisons are partly indirect.Meta-analysis · Adv Nutr

   Full breakdown →Sarcopenia explained →Calorie Deficit Calculator →Nutrition and Exercise Interventions to Improve Body Composition for Persons with Overweight or Obesity Near Retirement Age: A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials. Adv Nutr 2023
9. Nutritionpreliminary · human dataAdded 27 July 2026

   Five cups of coffee a day tracked lower cirrhosis risk

   Among 354,957 UK Biobank adults followed for a median of 13 years, those drinking 5 or more cups of coffee a day had lower rates of cirrhosis (hazard ratio 0.68), hepatocellular carcinoma (0.53) and liver-related mortality (0.58), with similar patterns for caffeinated and decaffeinated coffee. Imaging showed lower liver fat, iron and fibroinflammation with higher intake.

   ⚠What it shows: Large observational cohort, not a trial: coffee intake was self-reported by questionnaire in UK Biobank volunteers who are healthier than the general population. Models adjusted for demographic, behavioural, metabolic and genetic factors, but residual confounding and reverse causation cannot be excluded, so causation is unproven.Study · Clin Gastroenterol Hepatol

   Full breakdown →Caffeine guide →Caffeine Half-Life Calculator →Coffee Consumption and Improved Liver Outcomes: Clinical, Imaging, and Proteomic Evidence From the UK Biobank. Clin Gastroenterol Hepatol 2026
10. Nutritionpreliminary · human dataAdded 27 July 2026

    Real food, not shakes, lifted older adults' protein

    A meta-analysis of whole-food dietary interventions in adults aged 50 and over found they raised daily protein intake by 12.2 g/day compared with controls, with bigger effects when programmes ran longer, used individual counselling and set an absolute protein target.

    ⚠What it shows: Systematic review of 16 studies (n = 1712, 33% male) with a meta-analysis of 11 controlled trials (n = 1207) in community-dwelling older adults; protein intake was self-reported dietary data, the confidence interval was wide (+5.0 to +19.4 g/day), and muscle or strength outcomes were not the endpoint.Study · Nutr Rev

    Full breakdown →Sarcopenia explained →Protein Intake Calculator →Effectiveness of Whole Food Interventions on Protein Intake in Community-Dwelling Older Adults: A Systematic Review and Meta-Analysis. Nutr Rev 2026
11. Nutritionpreliminary · human dataAdded 27 July 2026

    Fibre-enriched tapioca pearls cut fat over 12 weeks

    In 50 obese women, 12 weeks of inulin-enriched tapioca pearls produced significant reductions in body weight, BMI, body fat mass, visceral fat, total cholesterol and LDL cholesterol compared with placebo pearls. The abstract reports the direction of change but not the size of it.

    ⚠What it shows: One randomised, double-blind, placebo-controlled trial in 50 women aged 20-50 with BMI at or above 27 or waist over 80 cm, run for 12 weeks; small, single-site, women only, and the abstract gives no effect sizes, so the reductions could be modest. One author is affiliated with the company behind the product. Needs larger and independent replication.RCT · J Food Drug Anal

    Full breakdown →Visceral fat explained →Body Fat Calculator →Evaluating the efficacy of I-fiber pearl on reducing body fat accumulation in obese females: A randomized, double-blind, and placebo-controlled trial. J Food Drug Anal 2026
12. Nutritionpreliminary · human dataAdded 26 July 2026

    Front-loading protein at breakfast missed on muscle

    Pooling seven randomised trials in adults aged 60 and over, adding protein or amino acids at breakfast did not improve lean mass, grip strength or lower-limb strength. The evidence was judged very uncertain, and in trials without exercise the extra morning protein was linked to slightly lower total daily energy intake.

    ⚠What it shows: Systematic review and meta-analysis of only 7 RCTs totalling 305 older adults; the authors rate certainty as very low, effect estimates all crossed zero, and they call for further high-quality trials.Review · Food Sci Nutr

    Full breakdown →Sarcopenia explained →Protein Intake Calculator →Protein or Amino Acid Intake at Breakfast for Muscle Mass Gain in Older Adults: A Systematic Review and Meta-Analysis. Food Sci Nutr 2026
13. Nutritionpreliminary · human dataAdded 26 July 2026

    Fat preference, not sweet, tracked worse outcomes

    In 182,181 UK Biobank participants, liking high-fat savoury foods was associated with a higher risk of type 2 diabetes (HR 1.14) and lung cancer (HR 1.10), while liking low-fat savoury foods tracked with lower risk of death, diabetes, cardiovascular disease and cancer. Sweet preference on its own was not linked to increased risk, and most associations were not explained away by BMI.

    ⚠What it shows: Observational prospective cohort of 182,181 UK Biobank adults with food liking captured on a single 9-point hedonic scale; hazard ratios are small, several confidence intervals reach 1.00, and stated preferences are not measured intake. Associations cannot establish cause.Study · Br J Nutr

    Full breakdown →All-cause mortality explained →Healthy Lifestyle & Life Expectancy →Associations between liking patterns for foods characterised by high/low fat content and sweet/savoury profiles and health outcomes: findings from the UK Biobank prospective cohort study. Br J Nutr 2026
14. Nutritionpreliminary · human dataAdded 23 July 2026

    Protein shakes help women build muscle, not lose fat.

    In a 2025 meta-analysis of nine trials in women, pairing a protein supplement with exercise gave small but significant gains in fat-free mass, muscle size and strength, but made no difference to fat mass or body-fat percentage.

    ⚠What it shows: Nine trials, 408 women aged 18 to 73. Muscle effects were small (about 0.45 kg fat-free mass) and there was no effect on fat loss; the authors call for more high-quality trials.Meta-analysis (9 RCTs) · n=408 · healthy women 18 to 73 · Front Nutr

    Full breakdown →Whey protein guide →Effects of multi-ingredient protein supplementation combined with exercise on body composition and muscle fitness in healthy women: a systematic review with multilevel meta-analysis. Front Nutr 2025

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