WorthDay Science Logbook
The evidence ledger: every study we track – published, in review, blog pending or flagged – in chronological order, together with the methodology behind every rating.
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59 studies shown
| Date Added | ID | Title | Category | Evidence | Tags | Status | Notes | Link |
|---|---|---|---|---|---|---|---|---|
| 2026-09-11 | S0063 | Barefoot walking is more stable in the gait of balance recovery in older adults | Health | 🔴 | Footwear / Barefoot | published | Original study | |
| 2026-09-04 | S0061 | Barefoot walking versus shod walking for persistent plantar heel pain | Health | 🟡 | Footwear / Barefoot | published | Original study | |
| 2026-09-04 | S0062 | Walking barefoot vs. with minimalist footwear - influence on gait in younger and older adults | Health | 🔴 | Footwear / Barefoot | published | Original study | |
| 2026-07-02 | S0060 | Gratitude journaling and subjective well-being in everyday life | Health | 🔴 | Behavior / CognitionMotivation | published | Original study | |
| 2026-06-27 | S0059 | Exercise versus antidepressant medication in older adults with major depression | Health | 🔴 | Behavior / CognitionMotivation | published | Original study | |
| 2026-06-06 | S0058 | CXCL10–IFN-γ axis and genistein in preclinical models of mRNA-vaccine-associated myocarditis | Health | 🔴 | VaccinationCardiometabolic | published | ||
| 2026-05-23 | S0057 | Exercise dose–response in adults with mild to moderate depression | Health | 🔴 | Behavior / Cognition | published | ||
| 2026-05-08 | S0056 | Calcium plus vitamin D in postmenopausal women: more kidney stones, limited fracture benefit | Health | 🟡 | VitaminsSupplementsVitamin DMinerals | published | Original study | |
| 2026-05-01 | S0055 | Monthly high-dose vitamin D in older adults: more falls with higher doses | Health | 🟡 | VitaminsSupplementsVitamin D | published | Original study | |
| 2026-04-24 | S0054 | Annual high-dose vitamin D3 in older women: increased risk of falls and fractures | Health | 🟡 | VitaminsSupplementsVitamin D | published | Original study | |
| 2026-04-17 | S0053 | Vitamin D3 supplementation in generally healthy adults: primary results of the VITAL trial | Health | 🟡 | VitaminsSupplementsVitamin D | published | Original study | |
| 2026-04-12 | S0048 | Chronic sleep restriction and cognitive performance in adults | Productivity & Balance | 🟠 | SleepBehavior / Cognition | published | ||
| 2026-04-05 | S0047 | Barefoot and minimalist footwear: effects on foot muscles and arch structure | Health | 🟠 | Footwear / Barefoot | published | ||
| 2026-03-29 | S0046 | Grounding ("earthing") and electrical body potentials in humans | Health | 🔴 | Earthing | published | ||
| 2026-03-15 | S0045 | Low-dose CT lung cancer screening in heavy smokers | Health | 🟡 | ScreeningCancer | published | ||
| 2026-03-08 | S0044 | Solid vs Puréed Foods: Structure, Satiety and Glycaemic Response | Health | 🔴 | NutritionFood structure | published | ||
| 2026-03-01 | S0043 | Chewing Frequency and Short-Term Energy Intake in Healthy Adults | Health | 🔴 | NutritionFood structure | published | ||
| 2026-02-28 | S0042 | General Health Checks in Adults: No Clear Benefit on Morbidity or Mortality | Health | 🟡 | Screening | published | ||
| 2026-02-26 | S0041 | PSA-Based Prostate Cancer Screening: Small Disease-Specific Benefit, No Clear Survival Gain | Health | 🟡 | ScreeningCancer | published | ||
| 2026-02-25 | S0040 | Mammography Screening for Breast Cancer: Mortality and Overdiagnosis | Health | 🟡 | ScreeningCancer | published | Original study | |
| 2026-02-13 | S0039 | E. coli NIZO Human Challenge With Protein Drinks and Neutralised Gastric Acid | Health | 🔴 | Infection modelsNutrition | published | ||
| 2026-02-12 | S0038 | Salmonella Typhi Human Challenge With Neutralised Gastric Acid | Health | 🔴 | Infection models | published | ||
| 2026-02-05 | S0037 | Adjuvant Chemotherapy After Surgery for Colon Cancer (Stage III) | Health | 🟡 | Cancer | published | ||
| 2026-01-20 | S0036 | Lifestyle of Chinese Centenarians in Chongqing | Health | 🔴 | Nutrition | published | Original study | |
| 2026-01-12 | S0035 | β‑Carotene Supplements & Lung Cancer in Male Smokers (ATBC) | Health | 🔴 | VitaminsSupplementsCancer | published | Original study | |
| 2026-01-11 | S0033 | Antioxidant Vitamins & Cardiovascular Disease in High‑Risk Women | Health | 🔴 | VitaminsSupplementsCardiometabolic | published | Original study | |
| 2026-01-11 | S0034 | Selenium, Vitamin E & Prostate Cancer (SELECT) | Health | 🔴 | VitaminsSupplementsMineralsCancer | published | Original study | |
| 2026-01-10 | S0031 | Multivitamins & Cardiovascular Disease in Men | Health | 🔴 | VitaminsSupplementsCardiometabolic | published | Original study | |
| 2026-01-10 | S0032 | Vitamin E & C and Cardiovascular Disease in Men | Health | 🔴 | VitaminsSupplementsCardiometabolic | published | Original study | |
| 2026-01-05 | S0030 | Sleep Restriction & Cognitive Performance | Productivity & Balance | 🟠 | SleepBehavior / Cognition | published | Original study | |
| 2026-01-02 | S0029 | Aerobic Exercise & Cognitive Function in Older Adults | Productivity & Balance | 🟠 | Behavior / Cognition | published | Original study | |
| 2025-12-29 | S0028 | Bound Water in Mammalian Hydration | Health | 🟡 | Hydration | published | ||
| 2025-12-27 | S0027 | Traditional Diets & Dental Health (Weston Price) | Health | 🔴 | NutritionDental health | published | ||
| 2025-12-23 | S0026 | Raw vs Pasteurised Human Milk & Neonatal Infections | Health | 🟡 | NutritionInfection models | published | Original study | |
| 2025-12-21 | S0025 | Cytopathic Effect Controls in Cell Culture | Health | 🟢 | Infection models | published | ||
| 2025-12-19 | S0024 | Habit Formation in Daily Life | Necessities & Routines | 🔴 | MotivationBehavior / Cognition | published | Original study | |
| 2025-12-17 | S0023 | Implementation Intentions & Goal Achievement | Productivity & Balance | 🔴 | MotivationBehavior / Cognition | published | Original study | |
| 2025-12-15 | S0022 | Social Relationships & Mortality | Social | 🔴 | Cardiometabolic | published | Original study | |
| 2025-12-13 | S0021 | Physical Activity & Mortality | Health | 🔴 | Cardiometabolic | published | Original study | |
| 2025-12-10 | S0020 | Dog Ownership & Health | Social | 🔴 | Cardiometabolic | published | ||
| 2025-12-07 | S0019 | Meat & Mental Health | Health | 🔴 | NutritionBehavior / Cognition | published | Original study | |
| 2025-12-04 | S0018 | Meat Supplementation in Kenyan Schoolchildren | Health | 🟡 | NutritionBehavior / Cognition | published | Original study | |
| 2025-12-01 | S0017 | Food Synergy vs Isolated Supplements | Health | 🔴 | SupplementsNutrition | published | Original study | |
| 2025-11-28 | S0016 | Multiple Micronutrients for Breastfeeding Women | Health | 🟠 | SupplementsVitaminsMinerals | published | Original study | |
| 2025-11-25 | S0015 | Antioxidant Supplements & Mortality | Health | 🟠 | SupplementsVitamins | published | Original study | |
| 2025-11-22 | S0014 | Topical Fluoride & Dental Fluorosis | Health | 🔴 | Dental health | published | Original study | |
| 2025-11-19 | S0013 | Fluoride Gels & Caries | Health | 🟠 | Dental health | published | Original study | |
| 2025-11-16 | S0012 | Fluoride Mouthrinses & Caries | Health | 🟠 | Dental health | published | Original study | |
| 2025-11-13 | S0011 | Oral Hygiene & Dental Caries | Health | 🟠 | Dental health | published | Systematic review of randomised controlled trials on personal oral hygiene and caries (Hujoel et al. 2018). Included trials manipulated toothbrushing, flossing or adjunct hygiene and measured new carious lesions clinically or radiographically. No clear, robust reduction in caries attributable to hygiene alone across the mixed-quality trials; diet, especially sugar, remains the dominant driver in WorthDay's interpretation. Diagnostic endpoints, many small and short trials. Low evidence (🟠). | Original study |
| 2025-11-10 | S0010 | Experimental Dental Caries in Rats | Health | 🟡 | Dental health | published | Controlled rat feeding experiments (Hartles 1960): natural sugar-free diet vs sugar-enriched diet under otherwise comparable conditions. Hard endpoint: presence, number and severity of carious lesions examined after the feeding period. Sugar-enriched diets produced far more caries, mirroring the rhesus monkey data. Rat model, older methodology with limited reporting on randomisation and diet detail. Moderate evidence (🟡). | Original study |
| 2025-11-07 | S0009 | Sugar & Dental Caries in Rhesus Monkeys | Health | 🟡 | Dental healthNutrition | published | Classic controlled feeding experiments in rhesus monkeys (reported in Nutr Rev 1946): natural sugar-free diets vs frequent or less frequent sugar exposure. Hard endpoint: directly observed dental caries. Sugar-free diets produced almost no caries; frequent sugar intake caused markedly more lesions, with frequency at least as important as total amount. Historical reporting, no modern randomisation or blinding, primate model. Moderate evidence (🟡). | Original study |
| 2025-11-04 | S0008 | Beverage Hydration Index & Bound Water | Health | 🟠 | Hydration | published | Randomised crossover trial in healthy young men (Maughan et al. 2016): fixed volumes of different beverages (water, milk, orange juice, soft/sports drinks) on separate days. Soft physiological endpoints over 4 hours: urine output and body-mass change, yielding a Beverage Hydration Index. Milk and orange juice produced better fluid retention than plain water, consistent with bound water. Strong lab control, but short window, narrow population, no long-term clinical outcomes. Low evidence (🟠). | Original study |
| 2025-11-01 | S0007 | Honey & Metabolic Syndrome | Health | 🔴 | NutritionCardiometabolic | published | Narrative/systematic review of cell, animal and small human studies on honey vs refined sugars in metabolic syndrome (Ramli et al. 2018). Secondary data only: mostly small, short-term studies with soft endpoints (lipids, weight, oxidative and inflammatory markers). Across studies honey often looked more favourable than refined sugar, but designs are heterogeneous and no large long-term trials with hard outcomes exist; publication bias possible. Hypothesis-generating only. Very low evidence (🔴). | Original study |
| 2025-10-29 | S0006 | Natural Honey in Diabetics | Health | 🟠 | NutritionDiabetes | published | Short-term randomised trial in type 2 diabetics (Bahrami et al. 2009): daily natural honey added to usual diet vs control, 8 weeks. Soft endpoints only: body weight, blood lipids, fasting glucose. Honey group showed modest weight loss, improved cholesterol/lipid fractions and no dramatic glucose deterioration; no hard clinical outcomes. Short duration, unblinded, small sample, no proper isocaloric null control. Low evidence (🟠). | Original study |
| 2025-10-27 | S0005 | Reducing Dietary Fibre & Constipation | Health | 🟡 | NutritionFood structure | published | Prospective intervention study in adults with chronic constipation (Ho et al. 2012): continue high fibre vs reduce fibre vs stop fibre over several weeks. Hard clinical symptom endpoints: bowel movement frequency, straining, bloating and pain, laxative need. The zero-fibre group improved most, the reduced-fibre group intermediately, the high-fibre group showed minimal change. Small sample, limited randomisation and blinding, adherence partly self-reported. Moderate evidence (🟡). | Original study |
| 2025-10-25 | S0004 | Caloric Restriction & All‑Cause Mortality in Monkeys (Wisconsin Study) | Health | 🟡 | Nutrition | published | Independent long-term controlled feeding experiment in a separate rhesus colony (Colman et al. 2014, Wisconsin): standard feeding vs approx. 30% caloric restriction started in adulthood. Hard endpoints: diagnosed age-related diseases and both age-related and all-cause mortality. Restricted monkeys had fewer and later age-related diseases and significantly lower age-related and all-cause mortality, with improved metabolic health. Complements S0003; animal model, no blinding, artificial standardized environment. Moderate evidence (🟡). | Original study |
| 2025-10-23 | S0003 | Caloric Restriction & Health in Rhesus Monkeys (NIA Study) | Health | 🟡 | Nutrition | published | Long-term controlled feeding experiment in adult rhesus monkeys (Mattison et al. 2012, NIA study): standard chow vs approx. 30% caloric restriction over many years. Hard endpoints: diagnosed age-related diseases (diabetes, cancer, cardiovascular disease) and mortality. Restricted monkeys developed age-related disease later and less often, with better metabolic profiles and less body fat; survival effects were mixed and sensitive to analytic choices. Animal model, staff unblinded, no null control. Moderate evidence (🟡). | Original study |
| 2025-10-21 | S0002 | Raw vs Heated Milk in Cats (Pottenger's Cats) | Health | 🟡 | Nutrition | published | Controlled multi-generation feeding experiment in cats (Pottenger). Hard endpoints: skeletal form, dental status, fertility, behaviour and survival. Cats on raw meat plus raw milk remained healthy and fertile across generations, while heated and heavily processed milks produced progressive skeletal deformities, dental decay, reproductive failure and shorter lifespans; some damage persisted into subsequent generations. Historical reporting: no modern randomisation or blinding, observers were unblinded, and it is an animal model (obligate carnivore). Moderate evidence (🟡). | |
| 2025-10-19 | S0001 | Raw Human Milk & Infant Health | Health | 🟡 | Nutrition | published | Experimental feeding trial in preterm infants (Lucas et al. 1992). Hard endpoints: measured IQ at school age (7.5-8 years). A higher proportion of mother's raw breast milk in the early diet was associated with significantly higher IQ, with a dose-response relationship; pasteurised human milk showed intermediate outcomes. Feeding policy was actively assigned, but reporting of allocation, blinding and controls is not fully CONSORT-level; no double blinding; no null control possible in this population. Moderate evidence (🟡). | Original study |
WorthDay Evidence Criteria
🟢 High
The hypothesis is tested in experimental studies that fulfil all applicable criteria: negative controls and null controls for every method and step; complete blinding (double-blind in human clinical trials without exceptions); full randomization and anonymization; adequate sample size; direct, hard endpoints whose interpretation does not depend on surrogate confirmation; absolute and relative effect measures with narrow confidence intervals; and all-cause mortality reported wherever mortality is relevant.
🟡 Moderate
The hypothesis is tested in experimental studies with direct, hard endpoints that do not depend on surrogate confirmation, but not all criteria for high quality are met.
🟠 Low
The hypothesis is tested in experimental studies with directly relevant endpoints, but whether an endpoint counts as reached still depends on additional indirect, surrogate or model-dependent confirmation criteria (e.g. diagnostic tests deciding case status), which can systematically bias the estimate.
🔴 Very Low
The hypothesis is examined in experimental studies only through indirect or surrogate measures (blood/urine assays, PCR/antibody tests, imaging, simulation, model-derived indices), or in non-experimental studies, or rests on expert opinion without systematic evidence.
Key principles
- •Hard vs surrogate endpoints: a change in a biomarker is not evidence of a clinical benefit.
- •A valid experiment includes negative controls and null controls; a placebo alone is not a negative control.
- •Relative risk reduction alone is insufficient; absolute measures (e.g. ARR) must be reported or calculable and their clinical relevance assessed.
- •Where overall mortality is relevant, cause-specific mortality alone is insufficient.
- •A well-conducted study that finds no effect confirms the null hypothesis and is not downgraded for it.
- •Ad-hoc assumptions cannot resolve confounds; assumptions imported from other studies do not become findings of the current study.
- •Consensus, authority, citation counts and years of use are not evidence.
Evidence-based living