Black people were as obese as white people in the 1950s, which is to say it was a very low percentage. It has nothing to do with non-whites but the fact that caloric intakes and sugar content in foods have increased. The 1950s was before fast food chains existed in large numbers. Before they put small restaurants out of business with their incredibly cheap products from their extensive supply chain. Those small businesses went belly up and these corporations just put a fuckton of sugar and fat in their products to get people addicted to their food.