Michael Pollan has a somewhat different take:
I would submit that the ideology of nutritionism deserves as much of
the blame as the carbohydrates themselves do – that and human nature. By framing dietary advice in terms of good and bad nutrients, and by
burying the recommendation that we should eat less of any particular
food, it was easy for the take-home message of the 1977 and 1982
dietary guidelines to be simplified as follows: Eat more low-fat foods.
And that is what we did. We’re always happy to receive a dispensation
to eat more of something (with the possible exception of oat bran), and
one of the things nutritionism reliably gives us is some such
dispensation: low-fat cookies then, low-carb beer now. It’s hard to
imagine the low-fat craze taking off as it did if McGovern’s original
food-based recommendations had stood: eat fewer meat and dairy products.
Many people eat healthy foods to assuage their consciences, and then they proceed to eat bad foods to satisfy their cravings. Start by boycotting the healthy stuff that doesn’t do you much good, like fruit, and you’ll munch on fewer pastries. You will feel the need for more conscience in your dietary portfolio, and maybe you’ll cut meat, dairy, and processed foods, which is what you should be doing. Do keep on eating those plants, though.