Evidence ratings

Every article carries a rating so you can see how settled a topic is before you read a word. Here is what each level means. The dots on the badge fill from one to three as the evidence gets stronger.

• Evidence Strong evidence

  Backed by multiple well designed human studies that point the same way, often including systematic reviews or meta analyses. The finding is well established.

• Evidence Moderate evidence

  Supported by several human studies, though the body of work is smaller or less consistent than a strong rating. The direction is reasonably clear.

• Evidence Mixed evidence

  Studies disagree, or the effect depends heavily on dose, population, or context. We show both sides rather than pick a winner.

• Evidence Emerging evidence

  Early research, small studies, or work that has not yet been repeated at scale. Interesting, but not settled. Read it as a signal, not a conclusion.

A rating describes the state of the research on a topic. It is not medical advice, and it does not describe results for any individual product. For how we assign ratings, see How we review.