How to Evaluate Health Information (Including Ours)
Being able to tell strong evidence from weak evidence is one of the most useful skills in navigating your own health — including reading everything else on this site with the right amount of confidence.
Last updated August 2026
Not all evidence is equal
Roughly in order of strength: systematic reviews and meta-analyses (which combine many studies) sit at the top, followed by randomized controlled trials (RCTs, where people are randomly assigned to a treatment or comparison group, which reduces bias), then observational or cohort studies (which watch what happens without assigning treatment, and are more prone to confounding), and finally case reports, expert opinion, and anecdote at the bottom. None of these are worthless — but they're not interchangeable either, and headlines rarely tell you which kind of study they're describing.
Sample size and replication matter
A single small study — even a well-designed one — is a data point, not a verdict. Look for whether findings have actually been replicated across multiple studies and populations before treating something as established.
“No data” is not the same as “bad for you”
Women's health has a well-documented history of being under-studied: the NIH didn't require women be included in clinical research until 1993, and conditions like endometriosis and PMOS remain comparatively underfunded relative to how common they are. When you see “not enough research yet” on a topic, that usually reflects this funding and research gap — not evidence that something is unsafe or doesn't work. Genuine uncertainty and a red flag are two different things, and it's worth learning to tell them apart.
Watch for these red flags
Claims that a single product or supplement “cures” or “reverses” a condition, testimonials presented as proof, anything suggesting medical guidelines are “hiding” something from you, and any pitch that never mentions a downside or interaction — all worth real skepticism.
How to actually check something
Look up the relevant medical society directly (see our sourcing page for which ones), search PubMed for a systematic review on the topic, or simply ask your provider what the current guideline says and why. All three are more reliable than a single article or social media post, including, honestly, ours — that's exactly why we tell you where our own information comes from.
Worth discussing with your provider
Educational information only — general patterns that vary by person. This is not medical advice, a diagnosis, or a substitute for care from your own clinician.
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