Home/Issues/Issue 05

In this issue

• Randomised double blind counterbalanced crossover trial Date verified

  Ketone monoester ingestion and cognitive and physical performance during exercise-heat stress

  Endurance trained men who took a ketone monoester alongside caffeine before 90 minutes of loaded walking in the heat lasted 8.9 minutes in a following run to exhaustion, against 7.0 minutes on an energy matched carbohydrate drink, and held their accuracy on the easier of two working memory tasks. Core temperature and heart rate were the same either way.

  Journal of the International · Lints et al. · University of South Carolina · 16 July 2026 · PMID 42460838

  ketonesheatcaffeineendurance-fueling
  8.9 min

  to exhaustion after the ketone drink, versus 7.0 minutes after carbohydrate
• Three level meta-analysis of 26 randomised crossover trials Date verified

  Effects of Acute Caffeine Supplementation on Physical, Sport-Specific, Physiological, Perceptual, and Cognitive Outcomes in Female Team-Sport Athletes: A Three-Level Meta-Analysis

  Pooling 26 crossover trials in female team sport athletes, caffeine produced a small edge in sprinting, jumping and change of direction, and made hard efforts feel easier. Skill based and cognitive outcomes showed nothing reliable, and no dose, timing or format pattern held up.

  Nutrients · Li et al. · Henan Sport University · 24 July 2026 · PMID 42588052

  caffeinewomen-athletesmeta-analysisendurance-fueling
  0.32

  Hedges g for physical performance, a small but consistent edge across the trials
• Four arm randomised trial with blinded outcome assessment Date verified

  Comparative Effects of Four Dietary Approaches on Symptom Severity and Quality of Life in Irritable Bowel Syndrome: A Randomized Controlled Trial

  Adults with irritable bowel syndrome were put on one of four eating plans for four weeks. Symptom scores dropped in all four, but fell further on the two low FODMAP plans than on traditional dietary advice, while quality of life improved by a similar amount in every group.

  Digestive Diseases and Sciences · Otay et al. · Gaziantep University · 20 July 2026 · PMID 42474623

  ibsgut-sciencenutrition
  61.5 %

  of the traditional advice arm hit a 50 point symptom drop, versus everyone else
• Randomised online choice experiment Date verified

  When do nutri-score labels shift food choices? Evidence for moderation by health-goal activation and prior beliefs

  Putting a Nutri-Score label on a pair of grocery products pushed Italian shoppers toward the better rated one. The push was biggest when the label agreed with what people already believed and they had just been asked which product was healthier.

  Journal of Experimental Psychology: · Hasni et al. · Paris Business School · 20 July 2026 · PMID 42475008

  labellingfood-policynutrition
  792 adults

  made 30 grocery choices each, with or without a front of pack label
• GRADE based systematic review and dose-response meta-analysis of 12 randomised trials The record carries a month level date of August 2026 with no day, so the exact publication day could not be confirmed.

  Ginger Supplementation and Blood Pressure in Adults: A GRADE-Based Systematic Review and Dose-Response Meta-Analysis of Randomized Controlled Trials

  Pooling 12 randomised trials, ginger supplementation was associated with a 5.03 mmHg drop in systolic and a 2.03 mmHg drop in diastolic blood pressure, with larger reductions in trials that used 2000 mg a day or more. The authors rate the certainty of their own evidence as low, because the trials disagree with each other.

  Journal of Human Nutrition · Karimi et al. · Bogomolets National Medical University, Kyiv · 1 August 2026 · PMID 42566667

  blood-pressuresupplementsmeta-analysiscardiovascular
  5.03 mmHg

  pooled drop in systolic pressure across twelve randomised ginger trials
• Prospective cohort study in UK Biobank Published 5 June 2026, before this issue's coverage window. Carried as a catch up.

  Plant-Based Diets, Ultra-Processed Foods, and Risks of Mortality and Major Chronic Diseases: A Prospective Cohort Study

  Published on 5 June 2026, this UK Biobank analysis of 124,836 adults found that people sticking closely to a healthy plant based pattern had lower rates of death, type 2 diabetes and cardiovascular disease whether that pattern was high or low in ultra processed food. The authors read this as diet quality mattering more than processing level.

  The Lancet Regional Health · Thompson et al. · Queen's University Belfast · 5 June 2026 · PMID 42294356

  ultra-processed-foodepidemiologynutritioncardiovascular
  124836

  adults tracked for up to 10.5 years across four plant based dietary patterns
• Mouse experiments, alongside a separate observational cohort of people Date verified

  Dietary intervention through bacterial-derived butyrate elicits anti-tumor activity and increases anti-PD-1 response

  In mice, adding the fermentable fibre inulin to the diet slowed tumour growth and made anti-PD-1 immunotherapy work better, and butyrate made by gut bacteria reproduced that effect on its own. In the study's separate group of 117 human lung cancer patients, fibre intake was not linked to survival at all.

  Gut Microbes · Benlaifaoui et al. · Centre de Recherche du CHUM, Montreal · 15 July 2026 · PMID 42454784

  gut-sciencefibermicrobiomeimmunology
  117

  lung cancer patients whose fibre intake tracked with neither survival measure
• Pooled analysis of 14 randomised trials in women having IVF or ICSI Date verified

  The effects of oral antioxidants on outcomes of assisted reproductive technology: a systematic review and meta-analysis of randomized controlled trials

  Pooling 14 randomised trials of oral antioxidants in IVF and ICSI, researchers found higher clinical pregnancy rates and more mature eggs collected. The live birth signal came from just three trials and disappeared when one of them was removed.

  Frontiers in Endocrinology · Qiang et al. · Beijing University of Chinese Medicine · 22 July 2026 · PMID 42558317

  fertilitymeta-analysissupplementsoxidative-stress
  3 trials

  supplied every live birth in the pooled estimate that headlines the paper
• Randomised, double blind, placebo controlled trial in men Date verified

  The Effects of Alpha-Lipoic Acid Supplement on Sperm Parameters and DNA Fragmentation in Couples with Recurrent Pregnancy Loss: A Randomized Controlled Trial

  In a 12 week randomised trial, men from couples with recurrent pregnancy loss who took alpha lipoic acid ended with lower sperm DNA fragmentation than those on placebo. Conventional semen measures did not separate the groups, and nobody tracked whether a pregnancy followed.

  International Journal of Fertility · Khadem et al. · Mashhad University of Medical Sciences · 27 July 2026 · PMID 42571056

  fertilityoxidative-stresssupplements
  40 men

  provided the DNA fragmentation result, out of 64 couples first enrolled

The headline check

What the press said, and what the paper underneath it supports. The paper is the source, not the article.

1. Rice bran compound may help ease irritable bowel symptoms

   ScienceDaily · 29 July 2026

   Paper: ferulic acid tested on strips of guinea pig intestine, Journal of Pharmacological Sciences, PMID 40543990 · published 14 May 2025

   There are no patients in this paper. It is guinea pig intestine in a tissue bath and a rat cell line, and the concentrations that worked are higher than eating rice bran could produce, which the coverage itself concedes further down.

2. Scientists tested 39 sweeteners and found unexpected gut effects

   ScienceDaily · 17 July 2026

   Paper: twenty five isolated bacterial strains and two cell lines in a dish, Molecular Systems Biology, PMID 42350810 · published 25 June 2026

   The words in vitro are in the paper's own title. Nobody swallowed anything. The coverage builds its hook around the millions of people taking a particular antidepressant, when no person was studied at any point.

3. Eating one avocado a day may lower heart disease risk

   ScienceDaily · 1 August 2026

   Paper: a randomised trial measuring lipoprotein particles in the blood, Journal of Clinical Lipidology, PMID 42364969 · published 12 June 2026

   This one is a real randomised trial, which makes the gap subtler. The outcomes were exploratory particle counts, not heart attacks. One measure moved and most were unchanged. The heart disease figure in the headline is a model applied to a marker, not something anyone observed.

4. Mediterranean diet may activate tiny proteins that protect the heart and brain

   ScienceDaily · 17 July 2026

   Paper: a cross sectional look at 49 people with an average age of 78, Frontiers in Nutrition, PMID 41883858 · published 10 March 2026

   Everyone was measured once, at the same moment, so nothing was activated by anything. The authors say the causal nature is undetermined. And no heart or brain outcome was measured at all, so protect has nothing in the study to point at.

5. Coffee may protect your heart but energy drinks could harm it

   ScienceDaily · 21 July 2026

   Paper: a scientific statement from the American Heart Association, Circulation, PMID 42473796 · published 20 July 2026

   This one is broadly faithful to the document it reports, which is a consensus statement rather than new data. The gap is confidence rather than substance: a statement that weighs evidence carefully becomes a headline with a verdict in it.

6. Eating within 8 hours may help keep the aging brain sharp

   ScienceDaily · 27 July 2026

   Paper: a conference abstract on time restricted eating in 47 women, NUTRITION 2026 conference abstract · published 27 July 2026 · not peer reviewed

   One cognitive domain out of several reached significance. Memory, learning, reaction time and multitasking did not. The headline picks the winner and leaves the rest out.