Every “Best” guide on Best for Nutrition answers one question: which supplement fits your situation, and why. This page explains exactly how we build those guides, how the BFN Score works, and what we will never do.
What We Actually Do (and What We Don’t)
Our guides are written by health professionals with dental and clinical nutrition training (see who writes our guides). Our work is label, research and evidence review. We read every product’s Supplement Facts and “Other ingredients” panel, compare the doses with the doses used in human studies, check third-party testing claims, and weigh the cost per effective daily dose.
We want to be precise about our limits:
- We do not run our own laboratory tests on products.
- We do not claim to have personally taken every product we list, unless a review says so explicitly.
- We do not accept payment from brands to include, rank or remove a product.
- We do not currently use an independent medical review board. Each guide is written by one of the authors below and checked against the sources it cites, which are listed at the end of every article.
- Our articles are educational and are not a substitute for advice from your doctor or pharmacist.
Step 1: Decide Whether the Supplement Is Worth Taking at All
Before we compare products, we look at the human evidence for the ingredient itself. Each guide includes a “Do You Actually Need” section and an Evidence Scorecard that grades the main uses as strong, moderate, limited or not supported. If the evidence is weak, we say so, even when that makes a product less likely to sell.
Step 2: Build the Shortlist
We start from the forms and doses that match the research, then look for products that:
- state exact amounts of each active ingredient (no proprietary blends that hide doses)
- use a studied form of the ingredient
- stay below the Tolerable Upper Intake Level where one exists
- show some form of quality control, ideally independent third-party testing
Products that fail these checks either do not appear or are listed under “Products We Didn’t Recommend”, with the reason.
Step 3: Score Each Product on Five Criteria
Every shortlisted product is rated privately on five criteria:
| Criterion | What we look at |
|---|---|
| Evidence fit | Is the form and amount of each active ingredient supported by human research for the purpose of the guide? |
| Dose accuracy | How close is each serving to the dose used in studies or to the RDA, without exceeding safe upper limits? |
| Purity, testing & additives | Independent certification (NSF, USP, Informed Choice) scores highest, then an ISO 17025 lab or a published certificate of analysis, then a general “third-party tested” claim, then GMP only. Points are deducted for flagged additives (see below). |
| Practicality | Pills per day, pill size, format, taste, dietary fit (vegan, gluten-free) and label clarity. |
| Value | Cost per effective daily dose compared with the other products in the same guide. |
Step 4: Turn the Ratings Into a BFN Score
The BFN Score is relative. It shows how the products in one guide rank against each other, not an absolute grade that can be compared across guides.
- We average the five criteria for each product.
- The product with the highest average receives 9.6/10 and the lowest receives 8.2/10. Everything else is placed proportionally in between.
- Every product in a guide already passed our shortlist, so even the lowest score means “a reasonable choice for some people”.
- Instead of printing five sub-scores, each review tells you where the product is strongest and where it is weakest, in plain words.
The BFN Score is never based on, or converted from, retailer star ratings or customer review counts.
How We Treat Additives
We read the full “Other ingredients” list and place each product in one of three tiers:
- Clean: common manufacturing aids such as cellulose, rice flour, vegetable capsules, silicon dioxide or magnesium stearate. At the amounts used in supplements, there is no good evidence these cause harm, so they cost no points.
- Note: ingredients that matter for some people, such as major allergens (soy, gluten, milk, fish), gelatin, added sugar or sugar alcohols in gummies, hidden caffeine, or kelp. We flag these for the people affected; they only lower the score when a guide targets that group.
- Flag: ingredients with a documented regulatory or safety concern, such as synthetic petroleum-based dyes (for example FD&C Red No. 40), titanium dioxide (banned as a food additive in the EU, still permitted in the US), partially hydrogenated oils, talc, high added sugar in gummies, or proprietary blends that hide doses. Each Flag lowers the purity rating, and we always explain why and cite the source.
We avoid scare words like “toxic” or “chemicals”. Our aim is to tell you what an ingredient does, who should avoid it, and how strong the evidence is.
How We Show Cost
Prices change daily, so we never print them. Instead, each product gets a cost tier based on the cost per serving on the date we checked:
- $ under $0.10 per serving
- $$ $0.10 to $0.25 per serving
- $$$ over $0.25 per serving
When a category is unusually cheap or expensive, we adjust the tiers for that guide and say so under the comparison table.
Sources We Rely On
We prioritize human clinical trials, systematic reviews and meta-analyses, and guidance from bodies such as the NIH Office of Dietary Supplements, the U.S. FDA, the European Food Safety Authority (EFSA) and national medical societies. Every guide ends with a numbered reference list. Brand marketing and customer reviews are never used as evidence that a supplement works.
How We Keep Guides Up to Date
Supplements are reformulated, discontinued and repriced often. We recheck labels, testing claims and cost tiers when we update a guide, and we record what changed in the update log at the bottom of each article. If you spot a label change or an error, please contact us and we will review it.
Who Writes Our Guides
Dr. Rashmi Byakodi, BDS is the editor of Best for Nutrition. She holds a Bachelor of Dental Surgery from Rajiv Gandhi University of Health Sciences, practiced in several dental clinics, and now writes full time about nutrition and supplements. She writes most of our “Best” guides.
Anju Mobin, B.Sc is a nutritionist with a B.Sc. in Home Science (Clinical Nutrition and Dietetics). She wrote many of our earlier guides and is the founder and editor of fitnesshacks.org.
Each article shows its author, the date it was last updated, and what changed. If you think something we wrote is wrong or out of date, please tell us.
How We Make Money
Best for Nutrition is reader-supported. When you buy through links on our site, we may earn an affiliate commission, including as an Amazon Associate, at no extra cost to you. Commissions never decide which products we include or how they rank. Read our full disclosure statement.
Safety First
Supplements can interact with medications and are not right for everyone, especially during pregnancy or breastfeeding, before surgery, or if you have kidney, liver or heart conditions. Every guide includes a safety section, but please talk to your doctor or pharmacist before starting a new supplement.