I just read the article, not the actual study, but I could think of about 10 things that put this in the "correlation is not causation" bucket if potential conf

I just read the article, not the actual study, but I could think of about 10 things that put this in the "correlation is not causation" bucket if potential confounding variables aren't closely controlled for. Things like: 1. Wealth. Wealth has been shown to be positively correlated with a myriad of better health outcomes. Are moderate coffee drinkers wealthier than average? 2. Job type. Are moderate coffee drinkers more likely to be office workers compared to blue collar. Or vice versa? 3. Exercise. Do people who drink moderate amounts of coffee exercise more? 4. Caloric intake. Do people who drink moderate amounts of coffee also eat fewer calories? Of course, with this one it's hard to tease out cause and effect - can coffee have a bit of an appetite suppressant effect? I've just learned over time that these types of nutritional studies often turn out to be wrong. Remember when we thought moderate drinking was good for you? Turns out that nearly all those studies were wrong due to other confounding variables (e.g. drinkers tend to be more social and there are a ton of health benefits from being social), and now the consensus belief is that alcohol itself is always a net negative, even in small amounts.