Short answer: the healthiest foods are the cheapest.
Caveat: they aren't prepared, so if you work fulltime or were never taught to cook or use them, they seem like an impossibility. Your comfort foods are defined by how you grew up, so it's often not a "default setting" for someone who grew up with junk food to reach for the carrot sticks.
These days, a lot of middle-class people buy prepared healthy food which costs a lot more but is without the prep time of doing it themselves. (Things like salad in a bag, premade hummus, etc.) I used to buy a lot of these until I moved to Asia. Now, if I want it, I have to make it. I think healthy eating/ food preparation should be part of any standard curriculum in any country. It would save a lot of money spent in the ER and on heart and vascular surgeries.
Odds are not in favor of that
How is middle class related to fat??
It still doesn't mean they'll be fat.
Actually I do. And it still doesn't mean they'll all be fat because of it.
More affluent people are more physically fit. Lower class people are the heavy drinkers, smokers, and obese prone.
Not sure about that. The healthiest foods are the cheapest foods. You know. Unprocessed food such as fresh produce, dried beans, rice, cereal, fruits, vegetables. I think it is more of a cultural thing and lack of education.