In our choice-laden grocery stores, with dozens of varieties of foods –
hundreds, perhaps – there seems to be a fairly clear awareness of what’s
good food, and what’s bad or junk food.
For example, we don’t need a book to remind us that, all else being equal,
a plum is a good food, whereas a tub of thick and creamy double-fudge ice
cream is a bad food.
Not bad tasting, of course; but, really, you won’t find many fit people
eating a vat of ice cream a day, for obvious reasons. So what does this
have to do with calories and energy?
It’s this: while you and I can evaluate our food choices and say that
something (like a plum) is a healthy source of energy, and something else
(like a tub of ice cream) is an unhealthy source of energy, the body doesn’t
evaluate. Really.
It sounds strange and amazing, but the body really doesn’t care. To the
body, energy is energy. It takes whatever it gets, and doesn’t really know
that some foods are healthier than others. It’s kind of like a garbage
disposal: it takes what you put down it, whether it should go down or not.
So let’s apply this to the body, and to weight gain. When the body
receives a calorie – which, as we know, is merely a label for energy – it
must do something with that energy.
In other words, putting all other nutrients and minerals aside, if a plum
delivers 100 calories to the body, it has to accept those 100 calories. The
same goes for 500 calories from a (small) tub of ice cream: those 500
calories have to be dealt with.