How FormulaTested Evaluates Supplements
This page explains how FormulaTested separates completed personal trials from research-based reviews, what is tracked during firsthand tests, how product facts and evidence are checked, and where the limits of each type of article are disclosed.
If you want to know whether you can trust a review before you read it, start here. You can also use the 12-point Supplement Review Transparency Checklist to audit any supplement review, including ours.
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.
Firsthand testing can add useful evidence, but it is not the only legitimate review format. FormulaTested also publishes research-based comparisons and formula assessments when personal testing is unavailable or unnecessary. The requirement is that the testing status is clear, product facts are checked, evidence is separated from brand claims, and personal outcomes are never invented.
THE BASICS
Products used in completed FormulaTested personal trials are purchased at full retail price by Marcus Reid. Some comparison and formula-analysis pages also discuss products that have not been personally tested; those pages should state that clearly and do not receive invented personal outcomes. No review placement is sold and no brand controls the conclusion or score.
Trial length depends on the product and the question being tested. Many completed trials run 30 days, while some run longer. The actual duration is disclosed on the review. Research-only or formula-assessment pages are not described as completed trials.
THE TESTING PROTOCOL
Where a formal baseline was recorded, the review says so. Not every historical trial used an identical pre-trial baseline, so FormulaTested does not retroactively claim that it did. The important rule is to disclose what was actually tracked rather than imply a cleaner protocol than the notes support.
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.
For a standard product trial, dosing normally follows the label unless the article explicitly documents a separate timing or stacking experiment. FormulaTested does not quietly change the protocol and then present the result as if it came from standard label use.
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.
For current structured personal trials, observations are recorded during the testing period rather than reconstructed later. Historical trials did not all use an identical logging template, so individual reviews disclose the records and limitations actually available instead of retroactively claiming a cleaner protocol.
HOW WE SCORE
FormulaTested separates firsthand trial scoring from research-based formula and buying assessments. A completed personal-test score can incorporate what was actually observed during the documented trial, while a research-only score is based on the current formula, dose quality, transparency, value, ease of use and evidence confidence. Research-only pages do not receive invented effectiveness or side-effect scores.
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 conclusion because a brand dislikes it. Research-only comparisons may cover products Marcus has not personally used, but those pages must distinguish research from firsthand testing and must not fabricate personal results.
FormulaTested’s standard is not whether a sentence was typed with or without software assistance. The standard is whether the underlying testing status, observations, product facts, sources, limitations and conclusions are accurate. Firsthand results are never invented, and researched claims should be distinguishable from personal experience.
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 a FormulaTested review needs correction, the standard is the documented protocol, current product label, cited evidence and clearly separated firsthand observations. Corrections should improve that record rather than protect a brand or an affiliate relationship.
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
Editorial pen name used by FormulaTested