I’m also curious about the source.
Re chocolate, i have a diabetic friend who is comfortable eating 80% chocolate but not chocolate with a lower cacao (and higher sugar) content. I think it’s generally true that chocolate is mildly healthful, but most chocolate bars have so much sugar and so little cacao that the sugar outweighs the cacao in terms of health impact. That’s true of basically all milk chocolate, but also true of many commercial “dark” chocolates.
I’ve never heard that you shouldn’t put milk in coffee for health reasons. I’m sure you can add enough cream to outweigh the benefits of the flavanoids in coffee, and also that that beverage would be delicious.