>Black people have more heart attacks,

Nothing to do with race, more about social standing. Black people tend to be less educated/affluent. Poor diet -> obesity -> heart attacks. 33% of whites are obese, while 48% of blacks are obese. Much more information can be found here: https://stateofobesity.org/disparities/

>white people are more likely to develop Seasonal Affective Disorder in the same geographic region, etc.

Again, nothing to do with race. White people tend to live in places like Alaska, Maine, etc. which have long and cold (and dark) winters.