All Guides & Reviews
Every supplement guide on Health Britannica, organized by type. Curated stacks, product roundups, single product deep-dives, and more — all using our 6 proposition value scoring system.
Curated Stacks
Complete supplement protocols organized by goal. Each stack includes our top product picks, synergy interaction maps, timing schedules, and daily cost breakdowns.
Stack Guide
The Foundation Stack: 5 Supplements Everyone Should Take First (2026)
Foundation
Athlete
Sleep
Longevity
The 5 supplements that form the base layer of every Health Britannica protocol, with exact brands and doses.
Stack Guide
The Cognitive Stack: Best Nootropics for Focus, Memory & Brain Health (2026)
Cognitive
Mood
Longevity
The 8 most evidence-backed nootropic compounds with synergy protocols for focus, memory, and neuroprotection.
Stack Guide
The Athlete Stack: Best Supplements for Strength, Endurance & Recovery (2026)
Athlete
Foundation
Performance-specific compounds that help you train harder, recover faster, and build more lean mass.
Stack Guide
The Sleep Stack: Best Supplements for Deep Sleep Beyond Melatonin (2026)
Sleep
Mood
Athlete
Targeting sleep onset, deep sleep architecture, and HRV improvement with compounds that work beyond melatonin.
Stack Guide
The Longevity Stack: Best Supplements for Healthspan & Cellular Aging (2026)
Longevity
Foundation
Cognitive
Compounds that target specific aging pathways: NAD+ decline, mitochondrial dysfunction, chronic inflammation, and cellular senescence.
Stack Guide
The Mood Stack: Best Supplements for Stress Resilience & Emotional Balance (2026)
Mood
Cognitive
Sleep
Adaptogens and targeted compounds that help your body handle stress without the crash-and-burn cycle.
Stack Guide
The Immunity Stack: Best Supplements for Immune Resilience (2026)
Immunity
Foundation
6 compounds with real clinical evidence for reducing infection frequency, shortening illness duration, and supporting immune cell function.
Stack Guide
The Glow Stack: Best Supplements for Skin, Hair & Nails (2026)
Glow
Longevity
5 compounds that address skin, hair, and nails from the inside out with real clinical trial evidence.
Product Roundups
"Best X supplement" guides with multiple brands tested and ranked. Each product is scored using our 6 proposition value system.
Product Roundup
Best Creatine Supplements in 2026: 10 Brands Lab-Tested & Ranked
Athlete
Foundation
Cognitive
We tested 10 creatine supplements for purity, mixability, and value. Monohydrate vs HCl — ranked with our 6 proposition value scores.
Product Roundup
Best Greens Powders in 2026: AG1 vs Alternatives Ranked by Cost & Quality
Foundation
We ranked 6 greens powders including AG1. Which is worth the price vs your Foundation Stack?
Product Roundup
Best Magnesium Supplements in 2026: 15 Brands Tested & Ranked
Foundation
Sleep
Cognitive
Athlete
Mood
Longevity
We tested 15 magnesium supplements across 6 forms. Ranked by absorption, purity, value, and which form matches your stack.
Product Roundup
Best Nootropic Supplements & Pre-Built Stacks in 2026: Ranked
Cognitive
Mood
We ranked the best nootropic supplements and pre-built stacks. DIY vs pre-built cost comparison included.
Product Roundup
Best Omega-3 / Fish Oil Supplements in 2026: 10 Brands Tested for Purity
Foundation
Athlete
Longevity
Mood
We tested 10 omega-3 supplements for EPA/DHA content, oxidation levels, heavy metals, and value.
Product Roundup
Best Pre-Workout Supplements in 2026: 5 Products Tested & Ranked
Athlete
We audited 5 pre-workouts against clinical evidence. Ingredient doses, pricing, and a DIY alternative at $0.55/serving.
Product Roundup
Best Probiotic Supplements in 2026: Strains, CFUs & Brands Ranked
Foundation
We ranked 6 probiotic supplements by strain evidence, CFU count, survivability, and value.
Product Roundup
Best Protein Powders in 2026: 12 Brands Lab-Tested & Ranked
Athlete
We lab-tested 12 protein powders for label accuracy, purity, and value. Whey isolate, casein, plant-based — ranked.
Product Roundup
Best Sleep Supplements in 2026: 8 Products Ranked
Foundation
Sleep
Mood
We ranked 8 sleep supplements. DIY sleep stack costs $0.31/day and targets three different sleep mechanisms.
Product Roundup
Best Vitamin D Supplements in 2026: D3+K2 Brands Ranked
Foundation
We ranked 5 Vitamin D3+K2 supplements on dose, form, third-party testing, and value. Why K2 matters and how much D3 you need.
Research Guides
Long-form articles exploring the science behind specific supplements. Clinical research analysis, dosage optimization, and evidence ratings.
Research Guide
Ashwagandha KSM-66: Benefits, Safety, Dosage & Best Brands (2026)
Ashwagandha is the most popular adaptogen — and the most controversial supplement we cover. Benefits, safety risks, dosage, and best KSM-66 brands.
Research Guide
Berberine: Benefits, Dosage, GLP-1 Connection & Best Supplements (2026)
Berberine is having a massive moment — driven by the 'nature's Ozempic' claim. That comparison is overstated, but the actual science is genuinely impressive.
Research Guide
Best Mushroom Coffee in 2026: RYZE vs Four Sigmatic vs MUD/WTR vs Everyday Dose
The mushroom coffee market hit $2.3 billion — but virtually all positive human studies used doses 4-10x higher than what's in a cup. We ranked 6 brands honestly.
Research Guide
Best Mushroom Supplements in 2026: Lion's Mane, Reishi, Cordyceps & More
Functional mushrooms are the fastest-growing herbal segment. But most cheap products are predominantly rice starch. We tested products across 5 species to find the real ones.
Research Guide
Best Turmeric & Curcumin Supplements in 2026: Bioavailability Tested
Standard curcumin has approximately 1% oral bioavailability. We tested 6 enhanced forms and ranked the best curcumin supplements by what actually gets into your bloodstream.
Research Guide
Caffeine + L-Theanine: The #1 Nootropic Stack — Dose Ratios, Clinical Evidence & Best Products (2026)
The most-studied nootropic combination in existence. A 2022 systematic review concluded it's 'likely a safe and effective cognitive enhancer.' Full protocol guide.
Research Guide
Lion's Mane Mushroom: NGF, Brain Benefits, Dosage & Best Supplements (2026)
Lion's Mane is the only dietary supplement with published evidence for stimulating NGF and BDNF production in humans. Full evidence review and best products.
Research Guide
Medical Cannabis in 2026: What 2,500+ Studies Actually Show About Benefits, Risks & Rescheduling
A sweeping JAMA review examined over 2,500 cannabis papers. This guide walks through every major condition, ranks the evidence, and explains the rescheduling situation.
Research Guide
NMN vs NR: NAD+ Supplements Compared — Which Actually Works? (2026)
NAD+ fuels mitochondrial energy and activates sirtuins. Two precursors promise to restore declining levels. This deep dive covers the biochemistry, evidence, and recommendations.
Research Guide
Rhodiola Rosea: The Adaptogen for Energy Without Stimulants (2026)
Rhodiola is the morning adaptogen — where ashwagandha calms, rhodiola energizes. Evidence for fatigue reduction, cognitive performance, and endurance.
Research Guide
Saffron for Mood: The Spice That Rivals SSRIs in Clinical Trials (2026)
Saffron extract at 30mg/day produces antidepressant effects comparable to fluoxetine in clinical trials, with significantly fewer side effects.
Single Product Reviews
In-depth reviews of specific products and brands, broken down with our 6 proposition value system.