How We Test Supplements at FormulaTested
Most supplement review sites do not have a testing methodology. They have an opinion and a word count. This page exists to show you exactly how every review on FormulaTested is produced, what we measure, how we control for variables, and why we think that matters.
If you want to know whether you can trust a review before you read it, start here.
WHY METHODOLOGY MATTERS
The supplement industry has a credibility problem. A large percentage of reviews online are written by people who received a free product, used it for a week, and wrote whatever the brand needed them to say. Another large percentage are written by people who never used the product at all and simply rewrote the label copy.
Neither of those things is useful to someone trying to make an informed decision about spending $60 to $130 on a supplement.
The only reviews worth reading are ones where the reviewer actually used the product, controlled for other variables, documented what happened honestly, and had no financial incentive to be dishonest about the result. That is what we try to do here. This page explains how.
THE BASICS
Every supplement reviewed on FormulaTested is purchased at full retail price by Marcus Reid. No free samples are accepted from brands or PR agencies. No review placements are sold. No brand has any involvement in what gets written or how a product is scored.
Every trial runs for a minimum of 30 days. Some products, particularly those containing ingredients like Bacopa Monnieri that require longer timelines to show full effect, are tested for 60 to 90 days before a review is published. The trial duration is always disclosed at the top of each review.
THE TESTING PROTOCOL
Before starting any trial Marcus establishes a one week baseline period. During this week he tracks the same metrics he will track during the trial, without taking the supplement. This gives a personal baseline to compare against rather than relying on memory or general impression.
During the trial itself the following variables are kept consistent:
Sleep schedule stays the same throughout the testing period. Wake time and sleep time are fixed to within 30 minutes of the target each day. Poor sleep affects cognitive performance, energy, and mood in ways that would contaminate the results of any supplement trial.
Diet stays consistent. No major changes to food intake, calorie targets, or macronutrient ratios during the trial period. Introducing a new diet alongside a new supplement makes it impossible to know which one is responsible for any changes.
Exercise stays consistent. The same type, frequency, and intensity of physical activity throughout the trial. This matters especially for energy, mood, and body composition products.
No other new supplements are introduced during the testing period. If Marcus already takes a consistent daily supplement like a basic multivitamin that has been part of his routine for months, it continues unchanged. Nothing new is added.
Dosing follows the manufacturer’s recommended protocol exactly. If the label says two capsules with breakfast, that is what happens every morning. No experimenting with higher doses, timing adjustments, or stacking with other products during the test period.
WHAT WE MEASURE
The specific metrics tracked depend on the product category. Here is how each category is measured.
For nootropics and cognitive supplements we track focus session length each day, which is the amount of time spent in continuous deep work before a voluntary break. We track reading comprehension using a consistent self-administered test taken at baseline and repeated at weeks two and four. We track subjective mental clarity on a 1 to 10 scale each morning and each afternoon. We note any side effects, however minor, on the day they occur.
For fat burners and weight loss supplements we track body weight each morning under consistent conditions, appetite ratings throughout the day on a 1 to 10 scale, energy levels morning and afternoon, and any physical side effects. We do not rely on weight alone as a measure because water retention, muscle changes, and natural daily fluctuations make single-metric weight tracking unreliable over 30 days.
For testosterone boosters and male health supplements we track energy levels, mood, subjective strength in consistent exercise sessions, and libido on a simple daily scale. We also note sleep quality which is directly affected by hormonal changes.
For sleep supplements we track time to fall asleep, number of night wakings, subjective sleep quality on waking, and morning alertness ratings. These are tracked daily throughout the trial.
For general wellness products including probiotics, greens powders, and similar supplements we track the specific outcomes the product claims to support, whether that is digestion, immunity, skin quality, or energy. Metrics are agreed before the trial starts and not changed midway through.
All data is recorded in a daily notes log on the day of observation. Nothing is reconstructed from memory after the fact.
HOW WE SCORE
Every review on FormulaTested uses the same six-category scoring system. Each category is scored out of 10 based on the trial data and ingredient research combined.
Effectiveness is the most heavily weighted category. It reflects the actual measured and observed results during the trial period, not what the product claims to do on the label.
Ingredient Quality reflects the quality and evidence base of the ingredients used. We look at whether the ingredients have genuine research behind them, whether the doses match what studies actually used, and whether the formula is transparent about exactly what is in it.
Ingredient Transparency reflects how openly the brand discloses its formula. A fully disclosed label with exact doses scores higher than a proprietary blend where individual ingredient amounts are hidden.
Value for Money reflects the cost per day relative to what the product actually delivers. An expensive product that genuinely works can still score highly here. A cheap product that does nothing scores poorly.
Side Effects reflects the personal experience during the trial. A product with no noticeable side effects scores a 10. Side effects are graded by severity and frequency.
Ease of Use reflects how practical the supplement is to take consistently. Dosing frequency, capsule size, taste where relevant, and whether the protocol is realistic for most people all factor in.
The overall score is a weighted average of all six categories. It is not rounded up for any reason. A 7.8 is published as 7.8.
WHAT WE DO NOT DO
We do not accept payment for positive reviews or higher scores. We do not change a review after publication based on brand feedback. We do not remove negative reviews because a brand complained. We do not publish reviews of products we have not personally tested.
We do not use AI to write reviews. Every word published on FormulaTested is written by Marcus Reid based on his personal trial experience and ingredient research. If that ever changes it will be disclosed clearly.
THE AFFILIATE RELATIONSHIP
FormulaTested participates in affiliate programs. When you purchase a product through a link on this site Marcus may earn a commission at no extra cost to you. This is how the site sustains itself.
We are transparent about this because we think hiding it is dishonest. What we want you to understand is that the affiliate relationship creates a financial incentive to recommend products, but it does not change what the scores say or what the reviews conclude. A product that scores 6 out of 10 stays at 6 out of 10. A product Marcus would not personally repurchase does not get recommended regardless of the commission rate.
If you ever feel a review on this site does not reflect an honest assessment, use the contact page and tell us. We take that seriously.
A FINAL NOTE
No testing methodology is perfect. Personal experience does not replace clinical trials. One person’s response to a supplement is not a universal result. What works well for Marcus may work differently for someone with a different baseline, different diet, different health status, or different goals.
What this methodology does provide is consistency, honesty, and a genuine attempt to separate what actually happened from what the brand wanted to happen. That is the standard we hold ourselves to on every review published on this site.
Marcus Reid Founder, FormulaTested