Body & HealthMental model

Ice cream sales and drownings rise together. Ice cream is innocent.

Two things occur together – that doesn't prove one causes the other. Often a third factor lies behind both: for ice cream and drowning, it's summer. In health studies such factors are called “confounders”: coffee drinkers used to smoke more often, which made coffee look more dangerous than it is for decades.

Useful: When you read “people who do X live longer”, ask: what else do those people do?

Source: en.wikipedia.org

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