How We Review & Score Supplements
No black boxes. No mystery algorithms. Every score on this site is calculated using the same transparent, weighted system explained below. If you disagree with a rating, you can check our math.
Our Scoring System (Out of 10)
Every product we review receives a single weighted score out of 10. That score is not a gut feeling or a "vibe check." It is the calculated result of five distinct categories, each evaluated independently and weighted according to how much it matters to you as a consumer.
Here are the five categories and their weights:
Ingredient Quality
This is the most heavily weighted category because ingredients are what you are actually paying for.
- Are the ingredients research-backed? We cross-reference every ingredient against PubMed clinical trials, systematic reviews, and meta-analyses.
- Are they at clinical doses? Many products include effective ingredients at 10-20% of the dose that actually produced results in research. We compare label doses to study doses.
- Are bioavailable forms used? Magnesium oxide vs. magnesium glycinate. Curcumin powder vs. curcumin with piperine. The form matters as much as the dose.
- Are there filler ingredients? Some formulas pad their ingredient count with compounds that have zero evidence (or negative evidence) to appear more comprehensive.
Label Transparency
You have a right to know what you are putting in your body and in what amounts.
- Full dosage disclosure: Does the label list the exact amount of every ingredient? Products hiding behind "proprietary blends" automatically lose points here.
- Third-party testing: Is the product tested by an independent lab (NSF, Informed Sport, USP, ConsumerLab)? Verification marks matter.
- Accurate labeling: Has the product been found to contain more or less of an ingredient than stated? We check available lab test data.
- Allergen and additive disclosure: Are fillers, flow agents, colorings, and potential allergens clearly listed?
Value for Money
The best formula in the world is worthless if it costs ten times what the ingredients are worth.
- Cost per serving: What are you actually paying per day or per dose?
- Cost vs. individual ingredients: Could you buy the same ingredients separately for less? We calculate the "DIY" price.
- Subscription traps: Does the brand use aggressive auto-ship programs? Is it easy to cancel?
- Refund policy: Is there a genuine money-back guarantee, or is it buried in fine print?
User Reputation
What real people say matters. But "real people" means real people -- not purchased reviews.
- Independent review platforms: We check Trustpilot, BBB, Reddit, and consumer forums -- not the brand's own website reviews.
- Review authenticity: We look for patterns of fake reviews (suspiciously similar language, review surges, verified-purchase ratios).
- Complaint patterns: Common themes in negative reviews (shipping issues, refund difficulties, side effects) are flagged.
- Community consensus: What do knowledgeable communities (r/supplements, r/nootropics, Longecity) actually think?
Company Trust
A great formula from a sketchy company is still a risk.
- Identifiable company: Can you find who actually makes this product? Is there a real business address, or just a PO box?
- Contact accessibility: Can you reach real customer service? Phone, email, live chat?
- Manufacturing standards: Is the product made in a GMP-certified facility? Is the facility FDA-registered?
- Regulatory history: Has the company received FDA warning letters? Been involved in lawsuits over product claims?
How the Weighted Score Works
Each category is scored independently on a 0-10 scale. The final score is the weighted average:
Final Score = (Ingredients × 0.30) + (Transparency × 0.20) + (Value × 0.20) + (Reputation × 0.15) + (Trust × 0.15)
This means a product with excellent ingredients but terrible value will be rated differently than a product with mediocre ingredients but great transparency. The weights reflect what we believe matters most: what is in the bottle (ingredients + transparency = 50%) comes before what surrounds the bottle (value + reputation + trust = 50%).
Scored Example: Athletic Greens AG1
Here is how our scoring system works in practice, using our review of Athletic Greens AG1 as an example:
AG1 scores well on company trust (Athletic Greens is a real, identifiable company with good customer service) and decently on user reputation. But it loses significant points on ingredient quality (many key ingredients are present at well below clinical doses), label transparency (it uses a proprietary blend structure), and value (at $79/month, the individual ingredients can be purchased for a fraction of the cost).
The math: (5.5 × 0.30) + (4.0 × 0.20) + (3.0 × 0.20) + (6.5 × 0.15) + (7.0 × 0.15) = 4.8 out of 10.
You can disagree with individual category scores. You cannot argue that the math was hidden from you.
Dose Analysis: How We Catch Underdosing
One of the most common problems in the supplement industry is "pixie dusting" -- including a clinically studied ingredient at a fraction of the dose that actually produced results, just so it can appear on the label. Here is how we visualize this in every review:
Dose vs. Clinical Research -- Athletic Greens AG1
Clinical doses sourced from peer-reviewed research on PubMed. "Clinical dose" = the amount used in studies that showed statistically significant results. Learn more about our methodology.
The green, yellow, and red color coding makes underdosing immediately visible. When you see a red "Pixie Dust" bar, that ingredient is present in name only -- the dose is too low to expect any meaningful effect based on the available research.
Our Research Process
Every review follows the same six-step process. No shortcuts, no exceptions, no "quick takes."
Product Purchase & Ingredient Analysis
We buy the product ourselves from a standard retail channel (Amazon, the brand's website, or a major retailer). We photograph the label, log every ingredient and its dose, and note any proprietary blend groupings that obscure individual amounts.
PubMed & Clinical Research Review
Every active ingredient is searched on PubMed. We focus on randomized controlled trials (RCTs), systematic reviews, and meta-analyses. We note the doses used in positive studies, the populations studied, the duration of trials, and any safety concerns. We do not cite animal studies or in-vitro studies as evidence of efficacy in humans.
Here is an example of how we cite research throughout our reviews:
Dosage Comparison (Product vs. Clinical)
For every ingredient with positive research, we compare the product's dose to the dose used in the studies. This is where most supplements fail. An ingredient might have strong evidence at 600mg, but if the product contains 50mg, that evidence does not apply.
We also check for bioavailable forms. Magnesium oxide has roughly 4% absorption. Magnesium bisglycinate has roughly 80%. The form used changes whether the stated dose is meaningful.
Real User Review Aggregation
We collect and analyze user feedback from independent platforms: Trustpilot, BBB, Reddit (r/supplements, r/nootropics, r/fitness), and consumer complaint databases. We explicitly exclude reviews found on affiliate sites, the brand's own website, and sponsored content pages.
We look for patterns: consistent complaints about specific side effects, refund difficulties, shipping delays, or changes in formulation. We also note when a product has suspiciously few negative reviews, which can indicate review management.
Price & Value Comparison
We calculate the cost per serving and compare it to the cost of buying the same ingredients individually from reputable suppliers (Nootropics Depot, Bulk Supplements, Jarrow, NOW Foods, etc.). This "DIY comparison" reveals the true markup you are paying for convenience and branding.
We also evaluate the refund policy (is it genuine or loaded with conditions?), subscription terms (easy to cancel or predatory auto-ship?), and whether multi-bottle discounts actually represent savings.
Final Scoring & Verdict
Each of the five scoring categories is assigned a score from 0-10 based on the evidence gathered. The weighted final score is calculated, and we write a clear verdict: who this product is for, who it is not for, and whether the science justifies the price.
Every review is dated. When new research emerges or a brand reformulates, we update the review and note the changes.
What We Don't Do
As important as what we do is what we refuse to do. These are non-negotiable editorial standards:
We don't accept payment for reviews
No brand has ever paid us to review their product, and no brand ever will. We choose what to review based on reader demand, market popularity, and our own curiosity.
We don't guarantee health outcomes
We are not doctors. We are researchers. Nothing on this site is medical advice. We evaluate products based on the quality of their formulation, not on promises about what they will do for you. Always consult your healthcare provider.
We don't recommend products we wouldn't take ourselves
This is our simplest test. If we wouldn't give it to a family member, it doesn't get a recommendation from us. High scores are earned, not bought.
We don't use fake doctors or fabricated credentials
We are supplement researchers, not physicians. We don't invent medical advisory boards, display fake "MD" credentials, or use stock photos of people in lab coats. If someone contributes to a review, their real background is stated.
We don't fabricate citations or testimonials
Every study we cite is linked to its PubMed entry. Every user testimonial references its source platform. If we cannot verify it, we do not publish it.
We don't inflate scores for products with affiliate programs
If a product scores a 3.2 out of 10, that is what we publish -- regardless of whether it has a generous affiliate commission. Our review of Athletic Greens AG1 above is a clear example: it is one of the most popular supplements in the world with a competitive affiliate program, and it scored below 5.
Our Affiliate Model -- Full Transparency
We believe you deserve to know exactly how we make money and exactly how it does (and does not) influence our work.
How affiliate commissions work
When you click a "Check Price" link on one of our reviews and make a purchase, the retailer pays us a small commission -- typically 5-15% of the purchase price. This comes from the retailer's marketing budget, not from your wallet. You pay the same price whether you use our link or not.
How we keep commissions separate from editorial
- Scoring happens first. Every review is researched, scored, and written before we ever check whether an affiliate program exists for the product.
- Low-rated products still get affiliate links. If a product scored poorly but the affiliate link exists, we include it -- because some readers will still want to buy it, and they should be able to check the current price easily. A link is not an endorsement.
- We recommend products with no affiliate program. Some of our highest-rated products have no affiliate program at all. We link to them anyway because our job is to help you find the best product, not to maximize our revenue.
- Every affiliate link is disclosed. Affiliate links are
marked with a
rel="sponsored"attribute, display a commission disclosure notice beneath them, and the site-wide banner at the top of every page links to our full disclosure policy.
Proof this works: low scores, active affiliate programs
The strongest evidence that commissions do not influence our scores is the scores themselves. Athletic Greens AG1 has one of the most generous affiliate programs in the supplement space. We scored it 4.8 out of 10 because that is what the evidence supports. We would rather lose affiliate revenue than lose your trust.
For our complete FTC-compliant disclosure, see our dedicated Affiliate Disclosure page.
Updates & Corrections
Science evolves. Products get reformulated. Companies change ownership. Our reviews evolve with the evidence:
- Reformulations: When a brand changes its formula, we update the review within 30 days and note what changed and how it affects the score.
- New research: When significant new studies are published that affect our assessment of an ingredient, we update all relevant reviews.
- Corrections: If we make a factual error, we correct it publicly with a visible correction notice. We do not silently edit reviews.
- Date tracking: Every review shows both its original publication date and its most recent update date. If a review has not been updated in 12+ months, we flag it for re-evaluation.
Hold Us Accountable
If you believe we have made an error, cited a study incorrectly, overlooked important research, or scored a product unfairly, we want to hear from you. Email us at hello@supplementskeptic.com with the specific issue, and we will investigate and respond.
We are not perfect. But we are transparent, and transparency means inviting scrutiny rather than avoiding it.