Until recently–on an evolutionary time scale–pretty much everyone was starving. Always.
Until the last century, there was no refrigeration. There was no transportation either. You want an orange in the winter? Bit of a problem, that. No idea can travel faster than the fastest horse. No produce moves very far either. If you can’t walk or ride from St. Louis to Honduras, you’ll have to do endure yet another day without OJ. Would you like a nice chicken salad sandwich? Good. Then go kill a chicken. But you better have another chicken to go kill a few days later because leftovers have a tendency to acquire bacteria that–if they don’t kill you–will make you wish they had.
As a result of being pretty much hungry pretty much all the time for generations untold, our fat cells evolved to store as much fat as possible. The fittest, those who could survive longer periods without food, survived. The survival dance was long periods of hunger followed by short periods of gorging bunches of calories. The predecessors of storage units were in our own bodies. “Shop till you drop” was preceded by “eat till you’re beat.”
Here’s a modern day example: an isolated population has been living is the south seas for centuries untold. They are usually hungry–few crops thrive on the rocky soil, they have access to a few conchs and some fish most of the year–but beyond healthy: no heart disease, no cancer, no tooth decay. Average life expectancy of 80 plus years. Within a generation of exposure to the west, the “all you can eat buffet” of “civilization” has lessened their life expectancy significantly. Long story short: with access to unlimited calories, they become fat and they die fat people’s deaths of heart attacks.
I learned about how our modern culture works against our evolutionary best interests from one of my best friends, an MD/PhD who works as a cardiologist. He told me about his patients who typically want to cut down on the number of medications he prescribes. “I don’t want to be taking 20 med’s a day,” they opine. “I’ll be happy to lessen the number of prescriptions,” my friend replies. “And I’ll lower the dosages too. But I have to ask you to lose 80 pounds first.”
It’s tough enough to lose the weight, but that can be done. Diet and exercise. Everybody knows how it works. But keeping the weight off, that’s the tricky bit.
“You know the woman in the ‘Lose Weight Now’ ads?” He asked me. “You know, the one who says, ‘I lost 80 pounds and kept it off for a year'”? I nodded. I had seen the ad. “You know the reason it’s always the same woman in the photograph?”
“Because there is only one woman who has ever lost 80 pounds and kept the weight off for a year.”
Being overweight isn’t a moral failing, the doctor told me. Once you’re overweight, it’s close to impossible to get the weight off and keep it off. You’re fighting millions of years of evolution. Long odds. Our fat cells are designed to retain fat. That’s how your ancestors survived. A world with access to unlimited food was unlikely. McCalories on every corner? Nah. But here we are with a fridge full of mayonnaise.
I wonder if our fat cells are addicted to food in the same way our brains can become addicted to drugs. I’ve often argued that addiction is addiction is addiction because dopamine is dopamine is dopamine. What the brain becomes addicted to varies–cocaine, alcohol, gambling, Internet pornography, my wife’s oatmeal raisin cookies–and some addictions are worse than others. (My advice? Talk to my wife about baking and stay away from meth-amphetamine.)
One thing is clear: once you start using–bad choice–it’s hard to stop, years, tears and dollars for treatment. The body “resets” at a new weight, the body get used to using, and it’s hard to get thin or sober again. That’s why I celebrate the recovery of my students who used to use. They’ve beaten long odds.