There can be some discussion today about what is actually "food". I'm not so sure it is such a bargain given the food related disease rates we have today. A lot of that is related to behavior in that people tend to go for the 'cheap calories'. That's why we have kids today that are both obese and malnourished.
Modern technology has also probably made us two-thirds less active than we were. The 1950s diet was still horrendous health-wise, with twice many eggs, tons of sugar, cooking fat, butter and oil and less nutritious meat like chicken than we use today. The stay at home housewife not only took in many less calories but burned actually burned them the hard way, through her domesticated lifestyle: three hours a day doing the housework, an hour walking to and from the shops downtown an hour on the shopping itself, another hour making dinner, play with the kids etc. Not a routine I would trade for the world but it does go to show the importance of exercise in the battle to maintain a healthy balance