Free · Backed by RCTs · No affiliate links
Browse supplements and health benefits backed by real clinical evidence — not marketing claims, influencer opinions, or animal studies.
The supplement industry has a trust problem
A podcast mentions a supplement. The host’s affiliate link goes to a brand that owns the host’s brand. You don’t trust the link, so you do the work yourself.
Half an hour on PubMed. Fifteen minutes on r/Nootropics. Ten more reading the Examine page you’re paying for. Another ten cross-referencing whether the effect everyone keeps quoting was actually shown in humans, in a randomized trial, for the outcome you care about.
You’ve done this for creatine. For ashwagandha. For NMN, until you gave up on it. The Sunday-night research session has become a tax — the price of not believing anyone with a shopping cart attached to their podcast.
We built Proof.fit so you stop paying it.
How it works
Step 1
Type the supplement and the outcome you’d take it for — does ashwagandha help anxiety, is creatine worth it for cognition, what’s the evidence on NMN.
Step 2
Every claim links to the underlying RCT — the gold-standard kind of human study. No paraphrase, no affiliate disclosure, no podcast clip standing in for evidence.
Step 3
Real evidence for the outcome you’re after? Worth a closer look. No evidence in humans yet? Skip it and keep your money. The whole loop fits in the time it takes the kettle to boil.
RCTs only
Every supplement on Proof.fit gets a Benefit Evidence table — what the trials actually measured, an evidence-strength label, the studies they came from, and the total participants pooled. If a popular claim has no human trial behind it, the table doesn’t pretend otherwise.
Two ways in
Start from one of 435 indexed supplements (ashwagandha, berberine, creatine, glycine…) or start from one of 93 benefit mappings (sleep quality, inflammation, heart health, antioxidant load…). Either way, you land on the same evidence — not a sales page.
Free at the lookup
Ask any question, read any trial card, browse the full supplement and benefit index without signing up. Proof.fit doesn’t sell supplements, take affiliate revenue, or write content for influencers. Free at the lookup is the whole point.
You walk away knowing whether a supplement is worth a closer look or not, with the trial open in a tab.
You stop being the unpaid researcher inside someone else’s affiliate funnel.
You see the gap between what’s been studied in humans and what’s just been marketed.
You get to a verdict without an account, a card, or a “start your free trial” wall between you and the citation.
Marcus K.
Software engineer, runs his own stack experiments
I cancelled Examine Insider after a month of using Proof.fit. Same trials, same rigor — but free at the lookup, and the chat answers the actual question I came with instead of making me skim a four-thousand-word article.
Aleksandra W.
Indie founder, building in public
Fadogia was on my next-month order because a podcast guest swore by it. Proof.fit pointed at the missing trials in humans in one paragraph. Saved me from a year of autopilot reorders.
Devon T.
Biology PhD candidate
How is a free consumer site doing better evidence triage than the supplement aisle of any pharmacy I’ve ever walked into?
Sara D.
Marketing director, Whoop user
I almost bought magnesium for sleep on a podcast tip. Proof.fit’s entry made it pretty clear the human evidence didn’t map to what I was about to add to my cart, so I closed the tab.
What Proof.fit doesn’t do
No affiliate revenue.
Supplement brands pay podcast hosts a cut for every bottle sold. We take none of that. Nothing on the page links to a checkout.
No mouse-only evidence.
Animal studies and lab-dish results are interesting, but they’re not proof in humans. If a popular claim only has mouse data, the page says so out loud.
No email gate.
Browse the index, ask the chat, read every trial card without giving us anything — no signup, no card, no "start your free trial".
No “research suggests” hedges.
Every effect on the page links to the actual trial it came from. Never paraphrased into a vague claim, never a podcast clip standing in for evidence.
Randomized controlled trials are the gold standard of medical research. They eliminate bias through randomization and control groups, producing the most reliable evidence available about whether a supplement does anything in humans. Proof.fit indexes RCTs from major medical research databases — not blogs, not podcasts, not animal studies, not single-arm observational pieces.
Ask whether ashwagandha helps with anxiety and you get a plain-English summary, the trials behind it (with author, year, and journal), the outcomes they measured, and an honest note when a popular claim isn’t backed by a randomized trial in humans. No paraphrase between you and the citation. No “click here to buy”. No newsletter wall.
One supplement, one question, one minute — and you’re done with the research session.
Try a question
Where to start
Chat
Type a supplement and the outcome you care about. Get the trials behind the claim, in plain English.
Open the chatBrowse
Start from the supplement — ashwagandha, berberine, creatine, glycine, NMN. Every entry shows the trials behind it.
Browse supplementsBrowse
Start from the outcome — sleep quality, inflammation, heart health, antioxidant load, immune support, digestion. Each one ranks the supplements with real evidence.
Browse benefitsOr just open the live product.
Go to Proof.fit →