By Eric Bryant & Shari Broder
Have you wondered just how paleolithic the “Paleo Diet” really is, and what does it have to do with the way we eat today?
There is a lot of debate nowadays about the diet our hunter-gatherer ancestors ate. So how did prehistoric humans actually eat? We have a pretty good idea based on modern foragers, the fossil record and our current make up.
Except for the dramatically different infant mortality rate between then and now, scientists believe humans were healthier when we ate the varied diet of a forager. It makes sense that eating many different fruits, nuts, berries, tubers, insects, fish and animals would give people a healthier variety of proteins, carbohydrates, fats and vitamins than someone who ate mostly bread, beer, wine and perhaps lamb, which may have been the average peasant diet in what is now the Middle East.
In most parts of the world, we now have easy access to a wide range of foods.
Hunter-gatherers, on the other hand, didn’t know where they might find their next meal. Unfortunately, we haven’t evolved fast enough to adjust to modern times, and it affects our eating to this day. Here’s why.
As a result of natural selection, our nomadic ancestors would die if they couldn’t find enough food, and their genes would not be passed to the next generation. So our current genetic makeup was likely determined by how our ancestors found food and what they did when they found it.
Can we blame overeating on our forager ancestors?
I have been reading a fascinating book on the history of humankind by Israeli scholar Yuval Noah Harari. In his chapter on our forager ancestors, he explains:
If a Stone Age woman came across a tree groaning with figs, the most sensible thing to do was to eat as many of them as she could on the spot, before the local baboon band picked the tree bare. The instinct to gorge on high-calorie food was hard-wired into our genes. Today, we may be living in high-rise apartments with over-stuffed refrigerators, but our DNA still thinks we are in the savannah. That’s what makes some of us spoon down an entire tub of Ben & Jerry’s when we find one in the freezer, and wash it down with a jumbo Coke.
You’re probably thinking, “so it’s not my fault that I want to overeat!” Well, from a genetic and evolutionary perspective, that’s probably right.
But not so fast! You’re not going to use this as an excuse for over-indulgence, are you? After all, I bet you don’t run or walk many miles per day to find your food. It’s probably less than twenty or thirty steps from the couch to the fridge, right? Most people reading this are fortunate enough not to have to worry about having enough food or going hungry. And you aren’t competing with baboons either!
No, to avoid overeating, we must use something else endowed to us by our hunter-gatherer DNA: our extraordinary brains.
Here’s the real issue. When it comes to food and eating, our brains can either help or hinder us, depending on what part of the brain we allow to be in the driver’s seat.
Our brain uses about 25% of our total energy, and wants to be as efficient as possible. That’s why we hear loud and clear the directions from the more primitive part of our brain where are habits reside, saying, “There’s food you like! Eat as much of it as you can before the baboons grab it!”
Our brains may also be accustomed to "habit eating” in response to negative emotions. To be efficient, it is easiest to just keep doing that, which means we’ll keep overeating and gaining weight.
But with some effort, including a willingness to feel our emotions and be mindful of our hunger and satiety, we can think our way out of this predicament and reverse the upward weight curve.
Thanks to the work of many brilliant scientists, we know that our brains have a high degree of neuroplasticity, probably, again, a result of our need to react to many different forces out in the wild. Neuroplasticity means we can actually rewire our brains. With commitment, awareness and tenacity, we can overcome eating behaviors and habits, and develop new, healthier habits. Here’s how.
We can use the more recently developed part of our brain, our prefrontal cortex, to disregard the messages that the older parts of our brain sends us, like “I better eat this because I don’t know where my next meal will come from."
Here are just a few of ways we can override our forager brain signals:
1. We can use our brains to plan ahead of time and decide what we will eat.
2. We can learn to pause before acting on an impulse to eat when we’re feeling negative emotions.
3. We can learn to feel our emotions, both positive and negative ones, instead of taking the edge off our bad feelings by eating.
We are wonderfully complex beings with a host of nature and nurture impulses to deal with. The rest of you has come in off the savannah, so bring your eating habits in, too!