Dieting scares our primitive brain

Woman obsesses over sandwichIf there is one thing human beings are good at, it’s adapting. In fact, we have a staggering ability to adapt to just about any environment.

About 10,000 years ago, we ate only what the earth offered us, which was limited to seasonal fruits and vegetables and whatever meat we could come by. Aside from occasional nuts or seeds, we could pack away for emergencies, food was in short supply during the long, lean winter months. Unlike most animals, humans couldn’t digest grasses or leaves to keep us going. Yet, while we had lost the claws and fangs of other predators, we more than made up for them with our brains’ cunning and creativity. Those brains needed lots of food to fuel them.

If we wanted to hunt meat and not be meat, we stayed focused. Hunting a large animal took many hours and sometimes days. This required stealth and strategy, but above all, motivation. Even when our early ancestors were cold or tired or sick, their survival depended on their desire to seek and consume food. Today, though our survival no longer depends on those things, it is always right below the surface. Motivation is instinctive.

The human brain has two parts—the old and the new, which is also called the cortex. The old brain is primitive; it operates quickly and automatically. The new brain, however, is deliberate. It thinks, plans and strategizes. It modifies impulsive behavior if it has a compelling reason to do so. Without the cortex, human beings would always act on instinct and respond automatically and predictably.

Some things have not changed: adequate food is still a basic need; we still need fuel and lots of it to keep going; and we are still motivated to seek and consume it. But there are two situations that kick our motivation into high gear: starvation and surplus. When we experience a sudden or dramatic decrease in calories, the alarm bells in our brains immediately begin clamoring. We think we’re starving.

This is one of the reasons we react so negatively to diets. The body and brain often interpret a diet as self-imposed starvation and respond with immediate and vigorous protests in the form of hunger pangs, cravings, and overall preoccupation with food. What is strange is that it isn’t only deprivation that kicks up the inner drive to eat and eat; it is also abundance.

Philippine Sailfin Lizard

The oldest part of your brain is the primitive, lizard brain.

How can this be?
Human history is strongly linked to the seasons. During the summer and early fall, food was probably plentiful with lots of lush vegetation and well-fattened animals. If humans had eaten only what they needed, it is unlikely that they could have stored enough fat to last them through the winter. So, as a safety precaution, their brains encouraged them to gorge on food while it was plentiful and to return as soon and often as possible to feast again.

Leap ahead to the twenty-first century. For most of us, seasonal starvation is a thing of the past, and abundance has no season. It is like an endless summer when it comes to food—a veritable pleasure island of plentiful, readily available, yummy things to eat. Our new brain knows that, but our old brain is still acting on intuitive signals. Feel hungry? Eat. Too much food? Eat more.

Where is our new brain when we need it? Will we always be at the mercy of the insatiable little muncher in our primitive brain? Fortunately, the answer is no. But just as our ancestors had to put their brainpower to work to become the hunter instead of the hunted, it is time for us to put our cortex in control.

Rather than adapt to our environment, we need to exert some control over it. We don’t have to respond to every impulse. Unless we develop new habits, our brains will tell us to keep eating for a winter that never comes. Most chefs and restaurant critics, who are surrounded by food at every turn, have trained their brains to understand that scarcity—fear of insufficient food—is extremely unlikely. They don’t allow their eating to be controlled by the bratty, primitive part of their brains. We can do that too by putting our cortex in control.

It’s time for the thinking part of our brains to pull up a chair at the feast and inject a bit of civility. It hurts a lot less than starvation; and, before we know it, our mad little muncher will become a mindful gourmet.

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