Melatonin Dose Guide: 1mg vs 3mg vs 5mg vs 10mg
Why lower doses often outperform higher ones — the dose-response science explained.
Supplement Comparisons: Every Form, Brand & Active Ingredient
The supplement aisle is designed to overwhelm. Magnesium glycinate, citrate, threonate, oxide, malate — which actually helps you sleep? Whey, casein, pea, soy — which builds the most muscle? We break down every major supplement on the same six-factor framework so you can pick what works for your goal.
Latest Flagship Comparisons
New evidence-based guides. Start here if you're new to the site.
KSM-66 vs Sensoril vs Shoden Ashwagandha
The three branded extracts side-by-side on withanolide content, dosing, and evidence.
Probiotic Strains Compared
L. rhamnosus, B. infantis, S. boulardii — strain-by-strain evidence for IBS, antibiotics, and immunity.
Berberine vs Metformin
How close is the OTC supplement to the prescription drug for blood sugar and PCOS?
Collagen Types I, II, III Compared
Hydrolyzed vs undenatured, marine vs bovine — which type for skin, joints, or hair.
BPC-157: What the Evidence Actually Says
Animal data, human data, legal status, and honest risk assessment for the most hyped peptide.
Vitamins & Minerals
Vitamin D2 vs D3
Ergocalciferol vs cholecalciferol — which raises your blood level faster.
Vitamin D Complete Guide
Dosing, testing, toxicity limits, and whether you need K2.
Magnesium Types Compared
Glycinate vs citrate vs threonate vs oxide vs malate — form-by-form guide.
Folate vs Folic Acid
MTHFR, methylfolate, and why form matters for some people.
Best Multivitamin Guide
What matters in a multi, and what's just marketing.
Eye Vitamins Guide
AREDS2, lutein, zeaxanthin for age-related macular degeneration.
Lutein vs Zeaxanthin
How these carotenoids differ and why both matter for eye health.
Protein & Performance
Whey vs Casein Protein
Fast digesting vs slow release — which for muscle, weight loss, pre-bed.
Vegan Protein vs Whey
Plant-based blends head-to-head against dairy protein.
Pea Protein vs Soy Protein
Amino acid profile, digestion, allergenicity, hormonal impact.
Collagen vs Protein Powder
Why collagen isn't a replacement for complete protein.
Best Protein Powder for Women
What matters in a women-targeted protein (and what doesn't).
Meal Replacement vs Protein Shake
When each makes sense and what to look for.
Mass Gainer vs Protein Powder
Calorie density, macros, and who actually needs a gainer.
Creatine Complete Guide
Monohydrate vs HCL, loading, timing, safety, and best brands.
Creatine Loading Guide
Should you load? Evidence-based answer.
Creatine for Women
Safety, hormonal effects, and why most women under-dose.
Sleep, Mood & Cognition
Melatonin vs Magnesium for Sleep
Different mechanisms, different use cases.
CBD vs Melatonin for Sleep
Evidence, dosing, and what the research actually says.
Melatonin vs GABA
Timing of action, absorption, and stacking strategies.
5-HTP vs Tryptophan
Serotonin precursors compared — absorption and safety.
Nootropics Guide
What works, what doesn't, and what's just caffeine in a trench coat.
Adaptogens for Stress
Ashwagandha, rhodiola, eleuthero, holy basil side-by-side.
Supplements for Anxiety
L-theanine, magnesium, ashwagandha, GABA — evidence-ranked.
ADHD Supplements
Omega-3, magnesium, zinc, iron — what clinical data supports.
Gut, Heart & Longevity
Omega-3 Benefits Guide
EPA vs DHA, fish oil vs krill vs algae, dosing for heart.
CoQ10: Ubiquinol vs Ubiquinone
Which form is better absorbed, and when it actually matters.
Turmeric vs Curcumin
Bioavailability, piperine, liposomal forms.
L-Glutamine vs Probiotics for Gut
Different mechanisms for leaky gut support.
NAC vs Glutathione
Which actually raises antioxidant levels.
MCT Oil vs Coconut Oil
C8, C10, C12 — what keto and brain claims are real.
Gut Health Complete Guide
Fiber, probiotics, polyphenols, and habit stack.
Low FODMAP Diet Guide
Elimination, reintroduction, and common mistakes.
Hair, Skin & Beauty from Within
Biotin vs Collagen for Hair
Which works and when it doesn't matter.
DHT Blockers Guide
Saw palmetto, pumpkin seed oil, finasteride — who should use what.
Nutrafol vs Viviscal
Hair-growth supplement brands compared ingredient by ingredient.
Fertility Supplements
CoQ10, myo-inositol, folate, DHEA — evidence-based picks.
Timing, Stacking & Strategy
Supplement Timing Guide
When to take each supplement for maximum absorption.
Supplement Stacking Guide
What goes with what — and dangerous combinations to avoid.
Carb Cycling Guide
For fat loss, performance, or hormonal support.
HIIT vs Steady-State Cardio
Training science applied.
Frequently Asked Questions
How do I pick between magnesium glycinate, citrate, and threonate?
Pick by goal. Choose glycinate for sleep, anxiety, and general absorption (highly bioavailable, non-laxative). Choose citrate for constipation relief (mild osmotic laxative effect). Choose threonate specifically for cognitive support (only form shown to cross the blood-brain barrier in meaningful amounts). Skip oxide unless price is your main constraint — it has very low bioavailability. Our full magnesium comparison covers dosing and side effects for each form.
Is whey or casein better for muscle building?
Whey is better post-workout (fast absorption drives acute muscle protein synthesis), and casein is better pre-bed (slow release feeds muscles overnight). For total daily protein target, they're interchangeable — your total daily intake matters more than timing for most people. Our full whey vs casein comparison covers digestion timing, amino acid profile, and specific use cases.
Should I take vitamin D2 or D3?
D3 (cholecalciferol) is more effective than D2 (ergocalciferol) at raising blood 25-hydroxyvitamin D levels. Studies show D3 is roughly 50-90% more potent, with a longer half-life. Choose D2 only if you're strictly plant-based and can't find a lichen-derived D3 (lichen D3 is vegan and equivalent in efficacy). See our full D2 vs D3 comparison.
Does creatine actually work, and which form is best?
Yes — creatine monohydrate is one of the most evidence-backed supplements in sports nutrition, with hundreds of trials showing strength, power, and lean mass benefits. Monohydrate (specifically Creapure® brand) is the best-studied and cheapest effective form. HCL and ethyl ester are marketed as "better absorbed" but don't beat monohydrate in head-to-head trials. See our full creatine guide.
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