Here’s an idea for an experiment:
Round up a bunch of big-brained apes who evolved for millions of years in a harsh environment of food scarcity.
Teleport them to a new, comfortable habitat where they have unrestricted access to as much highly-palatable, energy-dense food as they want, whenever they want.
No more hunger.
Let them spend their days sitting around.
No need to hunt or gather anything.
Give them magic screens to keep them busy and make them earn their keep while they’re sitting down. Have their superiors in the hierarchy consistently overload them with unreasonable demands to maximise their stress levels.
Deprive them of sleep. Increase above demands if necessary.
Provide them with more magic screens at home so they don’t have to go out to be entertained.
Give them energy-saving devices like cars, elevators and battery-powered pepper-grinders.
Wait a few decades and see what happens...
It’s only a few decades since the start of this evolutionary experiment yet we're already beginning to see some significant effects: one third of the world’s population is now overweight or obese.
Since the discovery of penicillin, we don’t generally die from infectious diseases like we used to 100 years ago*. So, we’re now much more likely to die from non-communicable diseases such as obesity, heart disease, diabetes, high blood pressure and some types of cancer which are all related to our excess energy consumption.
This means that they're all preventable.
I’m not suggesting it's easy to go against two of our strongest biological drives: to eat as many calories as we can get our hands on and to avoid unnecessary physical exertion.
But, it’s absolutely possible if we’re conscious of this mismatch between our genes and our environment, and try to mitigate it by behaving a bit more like our ancestors did.
The Hadza hunter gatherers of Tanzania still haven’t been teleported to our current habitat. They're known to down honey by the pint. This isn’t as gluttonous as it sounds when you consider that they’re unlikely to find it every week. And when they do, it’s often after having trekked tens of kilometres, while frequently experiencing hunger.
When we reach for the Ben & Jerry’s (or: insert favourite calorie-dense food here) we’re driven by the same primal impulses that drive the Hadza to gorge on honey.
But, the setting in which we experience these impulses differs in important ways. The few steps to the freezer don’t really count as exercise. When we eat it we're likely already stuffed instead of hungry. And when it runs out it’s not exactly challenging to find some more.
Gaining extra body fat is inevitable living in these conditions, and we can’t blame our genes. As Daniel Lieberman explains in his book, The Story of The Human Body:
‘Weight-gaining genes did not sweep through the human species in the last few decades. Instead, for thousands of generations, almost all the people who carried these genes had normal body weights, emphasising that what has most changed are environments, not genes.'
This is the first time in our evolutionary history that we haven't lived in an environment of food scarcity. It's also the first time we haven't had to physically exert ourselves to find and prepare food.
Being healthy in our current environment is possible but it requires moving when we don't want to and resisting the temptation to eat the calorie-dense foods that we're surrounded by.
The results of the experiment are clear. If we want to live long, healthy lives in this new world that we live in then we need to override the impulses of the ape brains that got us here.
*Ok, I hadn't predicted the Covid-19 pandemic when I wrote this