We should consider all research skeptically, but why does it seem particularly implausible that cocoa flavanols can enhance cognitive ability?

Other research:

https://scholar.google.com/scholar?q=cocoa+flavanols+cogniti...

I think the point here is not which prior to use for effect of chocolate, but how to account for the differences between actual and self-reported chocolate consumption, which itself might be correlated with cognitive ability.

Maybe people who ate chocolate but did not report it (because "eating too much chocolate is bad for you") tended to have lower cognitive ability - they did not realise that by reporting incorrect intake they introduced bias in the study.

There's caffeine and sugar in it, seems reasonable, plus the pleasure of it means more endorphins. That's like three direct up-regulators of brain function.

Well the researchers say in the article that sugar should impair cognition. Caffeine and feeling good are confounders, as they aren't unique to chocolate. The researchers are proposing that it is some kind of special ingredient in chocolate you can't really get anywhere else easily that enhances cognitive function.

Yeah, I agree that they should control for those things...

Also theobromine

And theophylline.

From wikipedia[1]:

Theophylline is naturally found in cocoa beans. Amounts as high as 3.7 mg/g have been reported in Criollo cocoa beans.

Medical uses[edit]

The main actions of theophylline involve:

- relaxing bronchial smooth muscle - increasing heart muscle contractility and efficiency; as a positive inotropic - increasing heart rate: (positive chronotropic)[1] - increasing blood pressure - increasing renal blood flow - anti-inflammatory effects - central nervous system stimulatory effect mainly on the medullary respiratory center.

Theophylline is also a metabolite of caffeine[2].

1. https://en.wikipedia.org/wiki/Theophylline 2. https://en.wikipedia.org/wiki/Caffeine#Pharmacokinetics