Which supplements have clinical evidence for chronic conditions? Which products deliver them without filler? And how do you build a stack that doesn't overlap. Doctor-reviewed. Independent. No affiliate links.
ConsumerLab tests for contamination. Examine.com aggregates studies. Nobody tells you which products deliver clinical-dose compounds without the filler you already take — or what a compound actually costs vs. its marketing label.
| ConsumerLab | Examine.com | closelook.health | |
|---|---|---|---|
| Purity testing | ✓ | — | — |
| Study aggregation | — | ✓ | ✓ |
| Evidence-level scoring | — | Partial | ✓ 5-Level Ladder |
| Product stack reviews | — | — | ✓ Condition-specific |
| Purity score (filler analysis) | — | — | ✓ ★-Rating |
| Price-per-compound transparency | — | — | ✓ |
| Doctor-reviewed | Lab team | Editorial | ✓ Physician |
| Zero supplement/pharma ads | — | — | ✓ |
| Overlap/interaction warnings | — | — | ✓ |
We analyze from three sides: from the chronic condition to the effective supplement, from the supplement to the clinical evidence — and from the manufacturer to the supply chain behind the label.
Which compounds have clinical evidence for specific chronic conditions? Which products deliver them in the right dose and form? How do you build a stack without overlap?
What does the research say about a specific supplement? For which conditions is there data? Which product delivers it in the studied form — and what does the compound cost vs. the marketing?
Who actually produces what you take? Own production or white-label? Branded raw materials or bulk imports? EU-certified or self-declared? The manufacturer profile reveals whether you pay for formulation — or for marketing.
Systematic analysis of age-related chronic conditions where long-term supplementation can make an evidence-based contribution. No acute conditions.
Glaucoma, AMD (dry & wet), cataracts, ocular microcirculation, digital eye strain
Endothelial function, atherosclerosis, blood pressure, homocysteine, lipid profile, vascular elasticity
Cognitive aging, neuroinflammation, Alzheimer's prevention, mitochondrial dysfunction in CNS
Osteoarthritis, osteoporosis, collagen metabolism, chronic joint inflammation
Insulin resistance, type 2 diabetes prevention, visceral fat, blood sugar regulation
Age-related immune decline, chronic low-grade inflammation, senolytics
Individual compound analyses. Study landscape, dosage, bioavailability, product comparison, price transparency. Every compound becomes a scorecard.
Updated quarterly. Each compound rated on evidence, safety, applicability, and overall assessment. Every entry doctor-reviewed.
| Compound | Primary Claim | Evidence | Rating |
|---|---|---|---|
| Metformin | Healthspan extension, TAME trial | L4 | |
| Rapamycin | mTOR inhibition, immunosenescence | L3 | |
| NMN | NAD+ precursor, cellular energy | L3 | |
| Spermidine | Autophagy induction, cognitive | L4 | |
| Taurine | Multi-system longevity, Columbia | L2–3 | |
| Resveratrol | Sirtuin activation, Sinclair thesis | L2 |
Five levels of scientific evidence. Every compound rated per indication. No marketing claims — only published research.
How focused is the product on its target indication? Products packing general vitamins receive a penalty — informed supplementers risk duplication with their baseline stack.
What does the active ingredient cost vs. what does the marketing cost? Quatrefolic® L-methylfolate costs the same whether it's in a €5 B-complex or a €97 "medical food." We normalize to price per day per core compound.
Three pathomechanisms. Three specialized products. Zero overlap. Zero general-vitamin filler.
| Mechanism | Product | Core Compounds | Evidence | €/mo. |
|---|---|---|---|---|
| Macula & Retina | Life Extension MacuGuard + Astaxanthin | Lutein 10mg, Meso-Z + Z 4mg, Saffron 20mg, Astaxanthin 6mg | L4–L5 | ~€20 |
| Eye Pressure (IOP) | Life Extension Eye Pressure Support | Bilberry 80mg (Mirtoselect®) + Pine Bark 40mg (Pycnogenol®) | L4 | ~€12 |
| Microcirculation & Hcy | Sunday Natural B-Complex Extra Forte | L-Methylfolate, B12 MH3A®, Nicotinamide, Citicoline, NADH | L4 | ~€9 |
For comparison: Nutravision (Australia) costs ~€45/mo. with underdosed carotenoids. Ocufolin® forte costs ~€30/mo. and covers only the homocysteine pathway. PreserVision AREDS2 overlaps with every multivitamin. Full review with 9 products →
Popularity is not evidence. But knowing what the market buys — and how it compares to clinical evidence — reveals where marketing wins over science.
Hitlist #2 worldwide. But which form? For which condition? At what dose? The form determines whether you're supplementing your brain, your gut, or your toilet. One compound, six realities.
Sleep · Muscle Relaxation · Stress · Anxiety
The glycine carrier itself has calming properties. Ideal for evening supplementation. Most doctor-recommended form.
Cognitive Function · Neuroprotection · Memory
Only form proven to cross the blood-brain barrier effectively. Branded as Magtein®. Low elemental Mg per capsule — not a general Mg replacement.
Blood Pressure · Heart Rhythm · Vascular Health
Taurine carrier adds cardiovascular benefit. Synergy between Mg and taurine for blood pressure and arrhythmia. Underrated form.
General Deficiency · Digestion · Constipation
Decent absorption. Osmotic laxative effect at higher doses — feature or bug depending on your goal. Widely available, affordable.
Energy Production · Muscle Pain · Fibromyalgia
Malic acid supports ATP production. Preferred morning form for people with fatigue. Limited but promising data for fibromyalgia.
Budget Products · Drugstore Standard · Antacids
~4% bioavailability. High elemental Mg on the label, very little absorbed. The form in most drugstore and budget products. Looks good on paper, performs poorly in practice.
| Product | Form(s) | Elem. Mg | Dose/Day | Purity | €/mo. | Manufacturer |
|---|---|---|---|---|---|---|
| NOW Magnesium Glycinatenowfoods.com · iHerb | Glycinate | 200mg | 2 tabs | ★★★★★ | ~€8 | NOW Foods 🇺🇸 |
| Life Extension Neuro-Maglifeextension.com | L-Threonate (Magtein®) | 144mg | 3 caps | ★★★★★ | ~€18 | Life Extension 🇺🇸 |
| Sunday Natural Mg-Komplexsunday.de | Glycinate + Citrate + Malate | 300mg | 3 caps | ★★★★ | ~€10 | Sunday Natural 🇩🇪 |
| Thorne Magnesium Bisglycinatethorne.com | Bisglycinate | 200mg | 2 caps | ★★★★★ | ~€14 | Thorne 🇺🇸 |
| Pure Encapsulations Mg GlycinatePharmacy / Practitioner | Glycinate | 120mg | 1–3 caps | ★★★★★ | ~€16 | Pure Enc. 🇺🇸/🇦🇹 |
| Cardiovascular Research Mg TaurateiHerb · Amazon | Taurate | 125mg | 2–3 tabs | ★★★★★ | ~€12 | Ecological Formulas 🇺🇸 |
| Doppelherz Magnesium 400DM / Rossmann / Amazon | Oxide | 400mg (label) | 1 tab | ★★ | ~€4 | Queisser Pharma 🇩🇪 |
Price estimates based on standard pack sizes at time of research. Elemental Mg = actual magnesium absorbed, not compound weight. Purity Score reflects focus on target compound vs. filler. Doctor-reviewed Q1 2026.
General guides tell you which form of Magnesium to take. They can't tell you whether it conflicts with your existing stack, your medication, or your specific condition. That's where a human expert comes in.
Form comparison, product tables, decision guides. Updated quarterly. Everything on this page.
Condition-specific stack reviews. Overlap warnings. Price transparency across full stacks. Like the Eye Health review — for every condition.
Personalized stack review by a longevity physician. Your supplements, your conditions, your medications — one conversation. Not an AI chatbot. A doctor who reads your labs.
Own production or white-label? Branded raw materials or Chinese bulk? EU-certified or US-GMP? Amazon SEO brand or 30-year compounder? Nobody maps this. We do.
| Manufacturer | Model | Scale | Sourcing | Certification | Price | Channel |
|---|---|---|---|---|---|---|
| Life Extension🇺🇸 Florida | Own + Contract | Global | Branded RM | cGMP, NSF | Quality-Value | D2C, Amazon, iHerb |
| Thorne🇺🇸 New York | Own Production | Global | Branded RM | cGMP, NSF, TGA | Premium-Medical | D2C, Practitioner |
| Sunday Natural🇩🇪 Berlin | Hybrid | EU Mid-Cap | EU + Branded | ISO 22000, HACCP | Quality-Value | D2C |
| Pure Encapsulations🇺🇸 / 🇦🇹 Nestlé Health | Own Production | Global | Branded RM | cGMP, Hypoallergenic | Premium-Medical | Practitioner, Pharmacy |
| NOW Foods🇺🇸 Illinois | Own Production | Global | Mixed | cGMP, NPA | Budget | Amazon, Retail, iHerb |
| Piping Rock🇺🇸 New York · 3rd Gen. | Hybrid Multi-Brand | Global | Mixed / Undisclosed | US-FDA GMP | Budget-Value | D2C, Amazon, Walmart, Retail |
| NutriVision Pro*🇩🇪 Amazon Seller | SEO Brand | National | Undisclosed | Self-Declared | Mass-Market | Amazon FBA only |
* Fictional composite example. Represents the typical profile of Amazon-native supplement brands with no disclosed production facility or raw material sourcing. Full manufacturer database in development.
Not every shop that sells supplements is a manufacturer. Some are pure marketplaces. Some mix own brands with third-party products. The channel determines price, curation, and transparency.
| Retailer | Type | Own Brands | Reach | Curation | Price Level | Key Trait |
|---|---|---|---|---|---|---|
| iHerb🇺🇸 California · Global Shipping | Multi-Brand + Own | California Gold | Global · 185 countries | Quality Gate | Value | Largest global supplement e-tailer. Own brands compete with listed brands. |
| Amazon🇺🇸 / 🇩🇪 / Global | Open Marketplace | Solimo, Amazon Elements | Global | No Curation | All Segments | Zero quality gate. SEO brands flourish. Reviews gameable. Caveat emptor. |
| Vitaminexpress🇦🇹 Austria · EU Focus | Curated Multi-Brand | VitaminExpress Own | EU (DACH focus) | Expert-Curated | Mid–Premium | Premium multi-brand selection plus own formulations. EU-compliant. |
| Life Extension🇺🇸 Florida | Manufacturer D2C | 100% Own | Global | Science-Driven | Quality-Value | Pure D2C plus wholesale. Only own products. Research-backed formulations. |
| Sunday Natural🇩🇪 Berlin | Manufacturer D2C | 100% Own | EU | Formulation-Focused | Quality-Value | D2C only. No Amazon. Branded raw materials. Clean label positioning. |
| DocMorris / Shop Apotheke🇩🇪 / 🇳🇱 EU Online Pharmacy | Pharmacy Marketplace | Some Private Label | EU (DACH focus) | Regulated | Mid-Range | Pharmacy trust signal. Mixed with OTC drugs. Limited specialist curation. |
| Piping Rock Shop🇺🇸 pipingrock.com | Manufacturer D2C | Multi-Brand (Own) | Global · 170 countries | Volume-Driven | Budget-Value | D2C but 3,000+ SKUs across own brands. Volume-over-depth model. |
Every review follows the same structured process. No manufacturer sponsorship. No affiliate revenue from supplement brands.
Identify the pathomechanisms of a chronic condition. Which biological pathways are therapeutically addressable?
Systematic literature review. Only compounds with published evidence from human studies (≥L3) are included.
Supplement facts dissected. Dosage, compound form, branded raw material, general filler, price per compound.
Every review checked for medical accuracy by a physician. Doctor's Notes add clinical context.
Closelook@Health receives no commissions, affiliate revenue, or sponsorships from supplement manufacturers.
Specialist in anti-aging & preventive medicine. Responsible for medical review of all analyses, evidence ladder classification, and doctor's notes.
Closelook Venture GmbH. Product analysis, price transparency, stack logic. The same analytical depth that Closelook readers know from financial market research.
Closelook@Health is an independent editorial product. Our analyses do not constitute medical advice, diagnosis, or treatment. If you have existing conditions, consult your physician. Referenced studies relate to the named compounds and do not represent therapeutic claims for the named products. We receive no compensation from the manufacturers analyzed. All prices are approximate and may vary.