Light summer reading. Well, maybe light is not the right word
Although obesity is nothing new in America, there have been recent attempts to look at the epidemic (that’s the CDC’s description) with a fresh focus. Yes, we’re too fat and have heart attacks and diabetes because we eat too much, but why do we eat so much more than other countries?
More specifically, why have we become so fat in only 20 years? The average adult weighs nearly 20 pounds more than his or her ’70s counterpart. The number of overweight children has doubled and the number of overweight teenagers has tripled. As a nation, we’ve added billions of pounds.
The New Yorker attempts to answer the second question via several reviews of what it calls “weight-gain books.” The first is The Evolution of Obesity, which argues that the downside of having a big brain is needing lots of energy to run it:
According to what’s known as the Expensive Tissue Hypothesis, early
humans compensated for the energy used in their heads by cutting back
on the energy used in their guts; as man’s cranium grew, his digestive
tract shrank. This forced him to obtain more energy-dense foods than
his fellow-primates were subsisting on, which put a premium on adding
further brain power. The result of this self-reinforcing process was a
strong taste for foods that are high in calories and easy to digest;
just as it is natural for gorillas to love leaves, it is natural for
people to love funnel cakes.
The problem with this theory is that while weight gain would have been an advantage for our ancestors mentally, it would have been a significant disadvantage physically, and a lion doesn’t care how smart you are if he catches you.
So the New Yorker looks at a different idea. The Fattening of America attempts to explain fatness from an economist’s point of view.