Research Library

93 studies & guides.
All cited.

Every entry rated by study design — RCT, meta-analysis, systematic review, or narrative review. New full articles added weekly. Use the filters or search to find exactly what you need.

93
Total entries
10
Full articles live
41
Meta-analyses
18
RCTs reviewed
11
Categories
Showing 93 entries
Meta 2024
Creatine

Creatine timing: pre vs post-workout — does it matter?

14 RCTs compared pre- vs post-workout creatine ingestion. Net difference is negligible. Consistency wins.

RCT 2026
Creatine

Creatine loading vs daily maintenance: full breakdown

Loading saturates muscles in 5–7 days vs 3–4 weeks on 5g/day. Performance outcomes at 4 weeks are identical.

Review 2024
Creatine

Creatine monohydrate vs HCl: is there actually a difference?

Four head-to-head trials. Monohydrate performs identically at one-third the cost. No evidence advantage for HCl.

Meta 2023 Coming soon
Creatine

Creatine and cognitive performance: what the evidence says

Emerging evidence in sleep-deprived and vegetarian populations. Effect in well-rested omnivores is minimal.

Review 2024 Coming soon
Creatine

Creatine safety in long-term use: 5-year data review

No kidney damage, no hair loss signal, no downregulation in healthy adults across all long-term studies reviewed.

RCT 2023 Coming soon
Creatine

Creatine and muscle glycogen: the under-discussed benefit

Creatine improves glycogen storage by 10–20% post-exercise, compounding its strength benefit with carbohydrate.

RCT 2022 Coming soon
Creatine

Water retention on creatine: myth vs mechanism

Initial weight gain (1–2 kg) is intracellular, not subcutaneous. It does not make you look bloated.

RCT 2023 Coming soon
Creatine

Creatine in vegetarians vs omnivores: why the difference matters

Baseline phosphocreatine is lower in vegetarians. Response magnitude is consistently larger in this population.

Review 2024 Coming soon
Creatine

Creapure vs generic creatine monohydrate: lab test comparison

Third-party analysis of 12 branded creatines. Purity was >99% in 9 of 12. Two failed heavy metal thresholds.

Meta 2023 Coming soon
Creatine

Creatine for women: same dose, same result?

Female-specific trials show identical phosphocreatine saturation and strength benefit at standard 3–5g/day.

Review 2024
Protein

Whey isolate vs concentrate: what you actually pay for

Isolate has higher protein per gram and lower lactose — relevant if lactose-sensitive. Otherwise marginal difference.

Meta 2024 Coming soon
Protein

Protein timing and MPS: does the anabolic window exist?

Window has widened to 4–6 hours in updated meta-analyses. Total daily intake matters far more than timing.

Meta 2023 Coming soon
Protein

How much protein do you actually need to build muscle?

1.6–2.2g/kg/day is the current evidence-based range. Going higher shows no additional muscle benefit.

RCT 2024 Coming soon
Protein

Plant protein vs whey: leucine content and MPS comparison

Plant proteins have lower leucine per gram. Blends (pea + rice) close the gap when dosed equivalently.

RCT 2023 Coming soon
Protein

Casein vs whey before bed: the overnight muscle protein synthesis data

Casein's slower digestion produces modest MPS elevation overnight. Effect size is real but small.

Meta 2024 Coming soon
Protein

Protein and satiety: why it's the most important macronutrient for fat loss

High protein diets increase satiety hormones and reduce spontaneous caloric intake by 400–500 kcal/day.

Review 2023 Coming soon
Protein

Protein quality scoring: PDCAAS vs DIAAS explained

DIAAS is the newer, more accurate scoring system. Whey scores ~1.09. Pea scores ~0.82. Soy ~0.91.

Review 2024 Coming soon
Protein

Heavy metal contamination in protein powders: what lab tests found

Consumer Reports and independent labs found lead, cadmium, and arsenic in 11 of 40 tested proteins.

Meta 2023 Coming soon
Protein

Protein intake and kidney health: the definitive answer

No evidence of kidney harm at intakes up to 2.8g/kg/day in people with healthy kidney function.

Review 2024 Coming soon
Protein

EAAs vs BCAAs vs whole protein: which actually drives MPS?

Whole protein containing all EAAs outperforms isolated BCAAs. BCAA-only supplements are nutritionally incomplete.

Review 2024
Vitamin D

Why most adults are deficient in vitamin D — and the dose to fix it

Intake ranges, D3 vs D2, and how to read your serum 25(OH)D test without panic.

Review 2024
Magnesium

Magnesium forms compared: glycinate, citrate, oxide, malate

Oxide has the worst absorption (~4%). Glycinate and malate lead for bioavailability.

Meta 2025 Coming soon
Magnesium

Magnesium and sleep quality: 2025 meta-analysis breakdown

18 RCTs, 1,400 participants. Significant effect on sleep onset latency — in deficient populations only.

Meta 2023 Coming soon
Magnesium

Magnesium and muscle cramps: evidence reviewed

Evidence is weak for exercise-induced cramps. Stronger signal for nocturnal leg cramps in older adults.

Meta 2023 Coming soon
Zinc

Zinc and testosterone: what the evidence actually shows

Zinc supplementation raises T only in deficient individuals. Supplementing replete individuals shows no effect.

Meta 2024 Coming soon
Vitamin D

Vitamin D3 vs D2: which form is worth taking?

D3 raises serum 25(OH)D 87% more effectively than D2 over 12 weeks. D3 is the clear choice.

Review 2023 Coming soon
Vitamin D

Vitamin K2 and vitamin D: why they're better together

K2 (MK-7 form) directs calcium to bone rather than arteries. Combination supplementation is well-supported.

Review 2024 Coming soon
Magnesium

How to calculate your magnesium deficiency risk

75% of adults fail to meet RDA through diet alone. Soil depletion, cooking losses, and absorption issues explained.

RCT 2023 Coming soon
Zinc

Zinc bisglycinate vs zinc gluconate: absorption comparison

Bisglycinate shows 43% higher plasma zinc than gluconate in head-to-head crossover study.

Review 2024 Coming soon
Vitamin B

Vitamin B12: who is deficient and which form to take

Methylcobalamin vs cyanocobalamin: retention and bioavailability compared. Vegetarians and vegans at highest risk.

Meta 2023 Coming soon
Iron

Iron supplementation: only if deficient, and which form

Ferrous bisglycinate outperforms ferrous sulfate on absorption and GI tolerance. Supplementing replete individuals is harmful.

Review 2024
Omega-3

Fish oil vs algae oil: EPA and DHA bioavailability compared

Algae oil is the direct source. Fish oil DHA bioavailability is equivalent. Oxidation quality varies.

Meta 2023 Coming soon
Beta-Alanine

Beta-alanine dosing protocol: why timing doesn't matter but loading does

4 weeks of consistent dosing required to saturate carnosine. Acute supplementation has no effect.

Meta 2024
Caffeine

Your caffeine dose is probably wrong — the 3–6 mg/kg evidence

Most pre-workouts use flat doses. Effective dosing is weight-based. Most users are under or overdosing.

Review 2023 Coming soon
Caffeine

Caffeine tolerance and cycling: the evidence-based protocol

Tolerance develops within 1–4 days of consistent use. A 7–10 day washout restores baseline response.

Review 2024 Coming soon
L-Citrulline

L-Citrulline vs citrulline malate: dose and form clarity

Pure citrulline is equally effective. Malate ratio in most products is not standardised to research doses.

RCT 2023 Coming soon
Caffeine

Caffeine and sleep: the half-life most people don't account for

Caffeine's 5–6 hour half-life means a 3pm dose still has half its effect at 9pm. Sleep quality impact quantified.

Guide 2024
Pre-Workout

Reading a pre-workout label without getting fooled

Proprietary blends, underdosed actives, and the four ingredients that actually move the needle.

Meta 2023 Coming soon
Electrolytes

Sodium and hydration during endurance exercise: the evidence

Sodium replacement rate matters more than total fluid intake for exercise over 2 hours. Thirst is not reliable.

Meta 2024 Coming soon
Nitrates

Beetroot juice and performance: a realistic effect size

2–3% improvement in time-to-exhaustion. Most effective in untrained individuals. High dose required.

Meta 2023 Coming soon
HMB

HMB for muscle retention: promising in theory, weak in practice

Effect sizes shrink dramatically once study quality is controlled for. Not recommended for trained athletes.

RCT 2023 Coming soon
BCAA

BCAAs during fasted training: the one use case with evidence

Pre-workout BCAAs in a fasted state reduce muscle protein breakdown. Marginal benefit when protein intake is sufficient.

Review 2024
Ashwagandha

KSM-66 vs Sensoril: which ashwagandha extract has better evidence?

KSM-66 has more high-quality human trials. Sensoril has a higher withanolide concentration but fewer RCTs.

Meta 2024 Coming soon
Ashwagandha

Ashwagandha and cortisol: how big is the real effect?

Average cortisol reduction of 23–27% in stressed adults over 60 days. Effect in non-stressed populations is minimal.

Meta 2023 Coming soon
Ashwagandha

Ashwagandha and testosterone: real signal or marketing?

Modest T increase (~15%) in stressed, untrained men. Effect does not replicate in trained athletes.

Meta 2023 Coming soon
Rhodiola

Rhodiola rosea and mental fatigue: what the trials show

Consistent signal for reduced mental fatigue during prolonged cognitive tasks. Standardisation across products is poor.

RCT 2024 Coming soon
Rhodiola

Rhodiola and physical endurance: separating signal from noise

Small improvements in time-to-exhaustion in some trials. Effect size is inconsistent across populations.

RCT 2024 Coming soon
Ashwagandha

Ashwagandha and sleep: the 2024 clinical trial data

600mg KSM-66 significantly improved sleep onset latency and quality over 8 weeks in a 150-person RCT.

Review 2023 Coming soon
Panax Ginseng

Panax ginseng vs American ginseng: different effects, same name

Panax improves cognitive performance. American ginseng shows different ginsenoside profiles and weaker evidence.

Review 2024 Coming soon
Lion's Mane

Lion's mane mushroom and nerve growth factor: current evidence

In-vitro evidence is promising. Human RCT data is limited to two trials with modest effect sizes.

Meta 2023 Coming soon
Fat Loss

Caffeine and fat oxidation: the dose-response relationship

200–400mg caffeine increases fat oxidation by 10–29% during moderate exercise. Effect diminishes with tolerance.

Meta 2024 Coming soon
L-Carnitine

L-Carnitine for fat loss: the gap between theory and evidence

Transport of fatty acids to mitochondria is sound mechanistically. Clinical fat loss effect in non-deficient adults is small.

Meta 2023 Coming soon
CLA

CLA (conjugated linoleic acid): does it actually reduce body fat?

Modest fat reduction (~0.5kg over 6 months). Effect only at 3.2g/day. Concerns around insulin resistance at high doses.

Meta 2024 Coming soon
Berberine

Berberine and blood glucose: the most important thing to know before taking it

Efficacy comparable to metformin in some trials. Drug interaction risk is serious and widely underreported.

Meta 2023 Coming soon
Green Tea

EGCG from green tea: the realistic fat loss effect

~3% increase in 24h energy expenditure. Meaningful only as part of a caloric deficit. Liver risk at high extract doses.

Review 2024 Coming soon
Fat Loss

Thermogenics: which ingredients have clinical support?

Caffeine is the only consistent thermogenic. Synephrine has a small signal. Most other ingredients lack human RCTs.

Meta 2023 Coming soon
Fibre

Psyllium husk and appetite suppression: the overlooked supplement

10–15g/day reduces post-meal hunger and lowers LDL. Better evidence than most marketed fat burners.

Review 2024 Coming soon
Metabolism

Metabolic rate and supplements: why most claims are wrong

Resting metabolic rate is largely fixed by lean body mass. Most supplements claiming to raise it fail in trials.

Meta 2024 Coming soon
L-Theanine

L-Theanine and caffeine: the 2:1 ratio and why it works

Theanine attenuates caffeine-induced anxiety without reducing alertness. Optimal ratio confirmed in 8 trials.

Meta 2023 Coming soon
Bacopa

Bacopa monnieri and memory: what 12 weeks of evidence shows

Consistent improvement in delayed word recall and processing speed. Requires 8–12 weeks for meaningful effect.

Review 2024 Coming soon
Citicoline

Citicoline vs alpha-GPC: the choline source comparison

Both raise acetylcholine. Citicoline additionally supplies cytidine for uridine synthesis. Alpha-GPC is faster-acting.

Meta 2024 Coming soon
Omega-3

Omega-3 and cognitive decline: what the prevention data shows

Strongest evidence in MCI populations. Effect in young healthy adults is minimal. DHA appears more important than EPA.

Review 2024 Coming soon
Nootropics

Nootropic stacks: what the combination evidence actually supports

Most combination products have no multi-ingredient human trials. Individual ingredient evidence is stacked without synergy data.

RCT 2023 Coming soon
Phosphatidylserine

Phosphatidylserine and cortisol: the evidence under exercise stress

400–800mg/day blunts cortisol response to intense exercise. Effect on general cognitive function is modest.

Review 2024 Coming soon
Magnesium

Magnesium L-threonate and brain magnesium: a different form for a different purpose

L-threonate crosses the blood-brain barrier more effectively. Cognitive benefit data is promising but early-stage.

RCT 2023 Coming soon
Creatine

Creatine and brain energy: the mechanism most people miss

Brain uses creatine-phosphate system too. Supplementation improves processing speed in sleep-deprived subjects.

Meta 2024 Coming soon
Caffeine

Caffeine and cognitive performance: dose, timing, and tolerance

Peak cognitive benefit at 100–300mg. Higher doses increase anxiety without further performance benefit in most.

Review 2023 Coming soon
Nootropics

Racetams and cognitive enhancement: separating hype from evidence

Piracetam has the most human data but most trials are in cognitively impaired populations. Minimal effect in healthy adults.

Meta 2024 Coming soon
Magnesium

Magnesium glycinate for sleep: protocol and realistic expectations

200–400mg elemental, 60–90 min before bed. Effect in deficient individuals is clinically meaningful.

Meta 2023 Coming soon
Melatonin

Melatonin dosing: why less is more

0.5mg is as effective as 5mg for circadian phase-shifting. Higher doses cause morning grogginess without added benefit.

RCT 2024 Coming soon
Ashwagandha

Ashwagandha and sleep latency: the 8-week RCT data

600mg KSM-66 reduced sleep onset by 35 minutes vs placebo. Effect was consistent at 4 and 8 weeks.

RCT 2023 Coming soon
L-Theanine

L-Theanine and sleep quality: mechanism and evidence

Increases GABA and reduces arousal. 200mg improves sleep quality without sedation. No dependency risk.

Review 2024 Coming soon
Recovery

Post-workout recovery: what the evidence supports

Protein, carbohydrates, and sleep are the only consistently evidence-backed recovery interventions.

Meta 2023 Coming soon
Tart Cherry

Tart cherry juice and muscle soreness: the DOMS data

480mg tart cherry extract reduced DOMS by 24% in six trials. Anthocyanin content drives the effect.

RCT 2024 Coming soon
Recovery

Collagen peptides and connective tissue: what 12 weeks of data shows

15g/day with vitamin C pre-exercise improved tendon collagen synthesis markers in a well-designed trial.

Review 2023 Coming soon
Melatonin

Melatonin for jet lag vs sleep onset: two different use cases

Jet lag: 0.5–3mg at destination bedtime for 3 days. Chronic sleep onset: 0.5mg 2 hours before target sleep time.

Meta 2024 Coming soon
Probiotics

Probiotic strains for IBS: what the strain-specific evidence shows

Bifidobacterium infantis 35624 and L. plantarum 299v have the strongest RCT support for IBS symptom reduction.

Review 2023 Coming soon
Fibre

Inulin vs psyllium: choosing the right prebiotic fibre

Inulin feeds Bifidobacterium selectively. Psyllium is better for cholesterol and bowel regularity.

Review 2024 Coming soon
Probiotics

CFU count in probiotics: does higher mean better?

10bn CFU is not better than 1bn CFU for most strains. Strain identity and viability at expiry matter more.

Meta 2023 Coming soon
Probiotics

Probiotics and antibiotic-associated diarrhea: strongest evidence use case

Saccharomyces boulardii and Lactobacillus rhamnosus GG both reduce AAD risk by ~50%. Take 2 hours apart from antibiotics.

Review 2024 Coming soon
Digestive Enzymes

Digestive enzyme supplements: who actually needs them

Useful in exocrine pancreatic insufficiency and lactose intolerance. Limited evidence for healthy individuals.

Review 2023 Coming soon
Gut Health

Leaky gut and supplements: separating mechanism from marketing

Intestinal permeability is real. Most supplements marketed for it have no human evidence. Zinc carnosine is the exception.

RCT 2024 Coming soon
Fibre

Resistant starch and gut microbiome diversity

RS2 and RS3 ferment to short-chain fatty acids in the colon, feeding beneficial bacteria and reducing inflammation markers.

Meta 2024 Coming soon
Collagen

Collagen peptides and joint pain: the clinical evidence reviewed

15g/day reduced knee pain scores in recreational athletes over 24 weeks. Effect in OA patients is also supported.

RCT 2023 Coming soon
Glucosamine

Glucosamine and chondroitin: does the GAIT trial settle the debate?

Combination showed modest benefit in moderate-severe OA only. Effect in mild OA was not statistically significant.

Meta 2024 Coming soon
Omega-3

Omega-3 and joint inflammation: the dosing that matters

≥2g EPA+DHA/day required for meaningful anti-inflammatory effect. Most fish oil capsules provide insufficient dose.

Meta 2023 Coming soon
Curcumin

Curcumin for joint pain: bioavailability is the problem

Plain curcumin has <1% bioavailability. Piperine or phospholipid complex forms required for clinical effect.

Meta 2024 Coming soon
Vitamin D

Vitamin D and bone density: the supplementation threshold

800–2000 IU/day maintains bone density in deficient adults. Effect above 50 nmol/L serum is minimal.

Review 2024 Coming soon
Testosterone

Natural testosterone optimisation: what actually moves the dial

Sleep quality, vitamin D, zinc (if deficient), and body fat percentage are the only modifiable factors with evidence.

Review 2023 Coming soon
Cortisol

Cortisol and overtraining: when more training becomes self-defeating

Chronic cortisol elevation from overtraining suppresses testosterone and impairs recovery. Biomarkers and warning signs.

Meta 2023 Coming soon
Estrogen

Phytoestrogens in supplements: should you be concerned?

Soy isoflavones at typical supplement doses do not feminise men or raise estrogen in clinical trials.

Meta 2024 Coming soon
Testosterone

Tribulus terrestris and testosterone: the evidence is clear

Nine controlled trials. No effect on testosterone levels or strength in trained men. The marketing is entirely unsupported.

Review 2023 Coming soon
Thyroid

Iodine, selenium, and thyroid health: the supplement interaction

Both iodine excess and deficiency impair thyroid function. Selenium is required for T4-to-T3 conversion.

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