Low SES in general speaks to ill health effects, indifferent to race or gender. As Crimson pointed out, access to good food and health care is gatekept by wealth, which in this country means that if you're poor, the potential to stay healthy or even take the steps to regulate chronic health issues is kneecapped. And also in this country, the poorest populations tend to be black and brown communities, which then begs the question of why that is. Fortunately, many in this thread have already linked to several studies showing why that may be.
It's not that poor whites, which are a healthy majority of working and unemployed poor, are less deserving of a fairer economic system, it's just that there are even more added stressors for black and brown poor people. Leveling out SES will have to include addressing that inequality as well.