It does not sound like an outcome that big coffee paid for it to be so:

Behaviourally, coffee drinkers exhibited greater impulsivity and emotional reactivity, whereas non-coffee drinkers demonstrated better memory performance.

The first paragraph of the introduction touts all the health benefits of coffee.

I don't necessarily deny these benefits but it feels weird for a scientific paper to hedge its bets like this.

> Moderate coffee consumption is associated with various health benefits, including reduced risks of type 2 diabetes, liver disease, cardiovascular diseases, and cancer3. In a large cross-sectional study of 468,629 individuals without clinical cardiovascular disease, light-to-moderate coffee consumption was linked to lower rates of all-cause mortality, cardiovascular mortality, and stroke incidence4. Furthermore, coffee intake is consistently associated with a reduced risk of Parkinson’s disease in a dose-dependent manner, across multiple human cohorts5,6,7. Meta-analyses have also found that coffee consumers face a lower risk of depression8,9, and one meta-analysis of cohort studies examining cognitive decline, showed that coffee consumption accounted for a 27% reduction in the incidence of Alzheimer’s disease

It's like they're starting off with "Now don't get me wrong. Coffee will cure cancer, but..."

Yeah it's telling how ISIC is covering this study. Their title is:

> New research reveals mechanisms behind coffee’s positive effects on the gut-brain axis

https://www.coffeeandhealth.org/health/media-content/news-al...

Or, maybe this is the cleaned-up interpretation

> It does not sound like an outcome that big coffee paid for it to be so:

Who said anything about big coffee? These guys might be a secret, anti-coffee organisation. /s

Ah yes, yet another in the long line of results which confirm our suspicion of water being wet to have been right all along. In this case it's something that anyone who has spent a significant amount of time around routine coffee drinkers and regularly consumed it themselves already took for granted.

Do they though? Any data on that? Also, the highly caffeinated people might also be sleep deprived, which impacts memory and emotional regulation