Biggest difference between food in the '50's and today is that they didn't use the chemical additives that we use today. They didn't wax the fruit and vegetables, douse it in pesticides, use glysophate as a dessicant to harvest the wheat, kill the green before digging the potatoes. They let the sun and cold do their jobs. 90% of todays supermarket food is GMO - from corn to soy to beet and cane sugar.
Eating in the 1950's is closer to eating today's organic food than anything else.
Today got to grow it yourself, or eat organic to eat as healthy as when you were a kid.