Who Is Behind These Reviews
Nutrition Comparison is a small team, not a content farm. Two people write and one reviews, and every guide names all three at the top so you can check our reasoning against our qualifications.
Theresa Monroe is a Seattle-based wellness coach and health editor. Armed with a degree in Public Health from Portland State University and a Certified Nutrition Coach credential, she spent over a decade helping families navigate complex supplement labels. She focuses on translating dense nutritional research into practical, honest reviews for everyday health.
Silas Bancroft is a nutrition researcher based in Boston, Massachusetts, specializing in dietary supplements for healthy aging. Holding a B.S. in Biology from the University of Massachusetts Boston, he evaluates clinical studies behind longevity vitamins, joint support formulas, and cognitive supplements. Silas provides clear, evidence-based supplement reviews to help seniors make informed wellness choices.
Zayden Maddox is a Denver-based sports nutrition coach specializing in workout supplements. With a B.S. in Kinesiology from Colorado Mesa University and a Certified Personal Trainer credential, he analyzes active ingredients in protein powders, pre-workout formulas, and muscle recovery vitamins. Zayden tests sports supplements to provide honest product reviews for active individuals.
What We Judge a Supplement On
Before any scoring happens, a product has to clear five questions. These are the questions we would ask about a bottle in our own cupboard, and they are the same for every category.
Active dose you actually get
The number that matters is the active compound per serving, not the total weight of the capsule. We normalize every product to the same unit before comparing.
Molecular form and absorption
Two products with identical doses absorb differently. Triglyceride versus ethyl ester, citrate versus oxide, and similar distinctions change what reaches your bloodstream.
Third-party testing
Whether an independent body verified the label. USP, NSF, IFOS, and Informed Sport all mean something specific, and we say which one applies rather than writing "tested".
Manufacturer track record
Recall history, FDA warning letters, GMP facility status, and whether the brand publishes certificates of analysis by lot or only on request.
Evidence behind the claim
Whether published research supports the dose on the label for the use the brand markets it for, and how strong that literature actually is.
Cost per unit of active
Bottle price tells you little. We calculate cost per gram of active compound and cost per day at the label serving, which reorders most categories.
The Six-Stage Process
Every guide runs the same sequence. It is deliberately mechanical: two editors working the same category from the same sources should reach a similar shortlist, because preference enters as late as possible.
Sweep the category
We list every product currently available in the category, not only the well-marketed ones, and record price, serving size, and stated actives from the live listing.
Read the Supplement Facts panel
Actives come from the panel, never from the front of the bottle. Anything without a readable panel or a published ingredient breakdown is cut at this stage.
Normalize the numbers
Everything converts to active nutrient per serving, per dollar, and per day. This is the step that stops a large serving size from making a weak product look strong.
Verify third-party testing
USP, NSF, and IFOS results are pulled per lot where a brand publishes them. Where certification is claimed but not evidenced, we record that as unverified rather than as tested.
Score and rank
The NC Score applies the same five weights across every product in the category. Ties break on cost per gram of active nutrient, never on brand recognition.
Second review, then re-check
A second team member checks dose, upper limits, and interactions against published literature before publication. Prices, labels, and certificates are revisited on each scheduled update.
What Goes Into an NC Score
The NC Score is an editorial rating out of 10 that weights five inputs. It compares products against each other inside one category. It is not a clinical prediction, and a 9.8 does not mean a product will work for you.
Milligrams of the compound that matters per stated serving, and whether reaching a research-relevant dose takes one capsule or six.
Molecular form, salt, or delivery system, and what absorption evidence exists for it rather than for the compound in general.
Independent testing for identity, purity, contaminants, and oxidation, weighted toward programs that publish per-lot results.
Price divided by total active nutrient in the container, which regularly reorders a category once serving sizes stop hiding it.
Full ingredient disclosure, no proprietary blends masking doses, clear allergen and excipient information.
Products that fall short of 8.0 do not make it into a published guide.
How We Decide Best Overall, Best Value and Best For
A ranked list is only useful if the labels mean something. Most roundups hand out "Best Value" to whatever is cheapest on the page. Ours are defined rules, applied after scoring, and only one product can hold each.
A product can win a label without topping the list, and the highest NC Score is not automatically Best Overall. If the top scorer costs four times the runner-up for a marginal gain in dose, the label goes to the runner-up and we say why.
How We Verify Our Picks
Before every publicationNo guide publishes with only one person's name on it. The review is not a rubber stamp on the rankings, which stay editorial. It is a check on the four things that can cause real harm if we get them wrong.
Sources We Rely On
Supplement Facts panels
The primary source for every number we publish, captured from the current label rather than an archived image.
Certificates of analysis
Per-lot results from USP, NSF, and IFOS programs where the brand publishes them, flagged where it does not.
Peer-reviewed literature
NIH Office of Dietary Supplements reviews, EFSA opinions, and primary trials for dose and safety context.
Live retail listings
Price, unit count, and bundle contents recorded at time of writing and re-checked on every update.
Where Our Method Stops
Stated limitationsA comparison built from documents can only tell you what the documents say. These are the gaps, and we would rather name them than let a confident tone imply we filled them.
- −We do not assay products ourselves, so we cannot confirm that a capsule contains what its label claims unless an independent program has tested it.
- −Third-party certification proves purity and identity, not efficacy. A tested product can still be a poor fit for your situation.
- −Evidence quality varies enormously by compound. Omega-3 has decades of trials; several longevity compounds have almost no human data, and our guides say so.
- −Formulas change without a name change. A figure that was accurate at publication can be wrong two months later, which is why the update date matters.
- −An NC Score compares products inside one category at one point in time. It is not a prediction about your body, your diet, or your medication list.
How We Keep Reviews Current
Supplement formulas change without a name change, and prices move daily. Every guide carries a published date and a last-updated date, and substantial changes are noted at the top of the article rather than made quietly.
Independence & How We Make Money
Affiliate disclosureNutrition Comparison is funded by affiliate commissions. When you buy through a link here we may earn a commission from the retailer, at no extra cost to you. That is the whole business model, and it comes with rules we hold ourselves to.
- No brand pays for inclusion, a position, an NC Score, or the removal of a criticism. There is no rate card because nothing is for sale.
- We buy no sponsored reviews and accept no free product in exchange for coverage.
- Commission rates are not a scoring input. Where two products score equally, the tie breaks on cost per gram of active, not on payout.
- No manufacturer sees a guide, a score, or a ranking before it publishes.
Several products we rate highly have no affiliate program at all. They stay in the guides, unlinked.
Limitations & Medical Disclaimer
Nothing on this site is medical advice, and our comparisons are not a diagnosis, prescription, or treatment plan.
Supplements interact with medication, and safe intakes differ by age, pregnancy status, kidney and liver function, and existing conditions. Talk to a doctor or a registered dietitian before starting anything new, especially if you take blood thinners, are pregnant or breastfeeding, or are managing a chronic condition. Statements here have not been evaluated by the FDA.
Our reviews describe what a label contains and what published research says about that ingredient. They cannot tell you what your body needs, and a high NC Score is a judgement about a product, never a recommendation for a person.
Method FAQs
Do you test the supplements in a laboratory?+
No. We compare labels, certificates of analysis from independent programs, and published research. Where a claim requires an assay to confirm, we cite whose assay it was rather than implying it was ours.
Can a brand pay to be included or ranked higher?+
No. We do not accept sponsored reviews, paid inclusion, or free product in exchange for coverage, and no brand sees a guide before publication. Affiliate commissions are paid by the retailer and do not vary by product.
Why do most published scores sit in the Good-to-Excellent range?+
Products that fail label transparency or verification checks do not reach scoring at all, and anything under 8.0 does not make it into a published guide. What survives that filter tends to cluster in the higher bands, but a Fair-tier product can still appear when it works well despite one clearly named trade-off, such as a higher cost per gram or a less bioavailable form.
How is the medical review different from fact checking?+
Fact checking confirms that a number matches its source. The medical review asks whether a dose is appropriate, whether it approaches an upper limit, and whether it interacts with common medications. Both happen, and they are separate steps.