Our hunter-gatherer heritage

I am almost always hungry. That sounds more dramatic than it is, but my food intake is somewhat remarkable, according to people around me. I have to eat every two hours, at least. Not much, but it has to be something. I cannot make it from breakfast to lunch without a snack. It’s a running gag at the office.

Yes, I have a fast metabolism and I do quite a lot of sports, but I think there is another, more generic explanation. While my male colleagues ask how my tapeworm is doing, it occurs to me that many females have quite a similar appetite. Men can survive on only three meals a day, because when they eat, they eat plenty. Women usually eat smaller amounts – only more often.

I mostly use our ancestors as an explanation for my eating frequency. Remember how, in history class, we learned about the hunters and gatherers? Years of human evolution have shaped us the way we are now, but our prehistoric heritage is still there – also when looking at our eating patterns. In the Stone Age, women were picking fruit in the forest. While gathering, they could eat small amounts of whatever they collected, the whole day long. One berry in the basket, one in the mouth (well, at least that’s how I imagine it). The men had a different day job, involving quite some endurance running while throwing spears. Therefore, the hunters had to stack carbs in the morning: to make it through the day without snacks in between. Women did not need to build these energy reserves, so their bodies developed differently.

I thought I read this years ago in an academic article, but I cannot find it anywhere. I googled for an hour, but my story lacks evidence. So there’s a slight chance I made it up myself, but it all makes perfect sense, doesn’t it? And there’s more (that is actually supported by research). Men are usually better at navigating, while women pay more attention to detail. Hunters were not looking at the flowers along the trail, while chasing some wild animal. They developed a better sense for direction, having to remember their way back home while running. Meanwhile, the women were doing their jobs at a slower pace, developing better short-distance focusing. “In simple terms, women are faster at finding things in the house, and men are faster at finding the house,” a researcher explains. It’s just the way our brains developed differently. A result of our evolutionary past.

Fight or flight?

So men were fighting bears with spears and women looked for berries and cherries, but the reality was obviously far less poetic. When encountering a predator, our ancestors faced a serious life threat. Luckily, there was a mechanism in place to optimize their response and thereby maximize chances to stay alive. In case of an emergency – regardless of gender – they experienced stress. 

Let’s take a look at the stress of our ancestors. This is what happens: first you need to make a lifesaving decision in a split-second: fight or flight? Second, your body needs to get ready fast for the critical action: either run for your life or battle a hungry animal. As a result the heart beat rises, the breathing fastens, our sight and hearing sharpens, all to prepare the body for combat. Stress suppresses the digestive, reproductive and immune systems, in order to save all valuable energy to deal with our highest priority: survival.

Nowadays we do not often encounter dangerous species to run from (horrible bosses or blind dates from hell not included). But we still have our stress response. The “stressors” in our lives have changed and can take many different forms. Traffic, financial problems, a break up, job insecurity, sickness, worries about a loved one, working too many hours, you name it. Usually, they are not life threatening and most stressors are not physical but mental. “Run for your life” is not that common anymore.

Nevertheless, our nervous system has not evolved as much as you would think. Regardless of the cause, the response of our body to stress remained quite similar to the one of our ancestors. “Inside of each modern human is the nervous system of a caveman,” I read. Whether the stressor is physical or mental, real or imagined: whatever happens, we only have one response to stress. And it is the same one as thousands of years ago. Our body prepares for a fight or flight.

Acute versus chronic stress

Stress is a very useful mechanism, still. Think about it: if you have to give a presentation in front of 100 people or you nearly escape a car accident, our optimal focus and physical responsiveness help us to save the day. Nonetheless, we have to distinguish between acute and chronic stress. Acute stress is a normal part of everyday life. The problem occurs when it becomes chronic stress.

Research states that our stress response system was not designed to be constantly activated. It was meant to be short-term and historically it was. Fight a bear and then basta – you either survived or you didn’t. When the danger had passed, stress levels of our ancestors returned to normal. Nowadays, it seems that we suffer from long-term stress: our acute stress response won’t turn off anymore. We feel pressured all the time. The release of our stress hormones keeps on going and this causes problems. Memory loss, weight gain, insomnia, depression, heart diseases. I am not going to dive into all kinds of physical and mental disorders that can be caused by a structural, excessive level of the stress hormone in our bodies, but it is not something to think too lightly about. Chronic stress has an adverse effect on our general health.

I think we all know what lies at the heart of chronic stress. It is “our tendency to commit ourselves to personal goals that are too many and too high.” While we often think that high demands are coming from outside, Nesse and Young conclude that “much stress arises, ultimately, from a mismatch between what we desire and what we can have.” Put differently, our stress is not caused by external factors, but by the things we ask from ourselves. The hungry bear we perceive, is not seldom created by our own minds.

Stress and mindfulness

Stress is something of all times. I am not saying we cannot worry nowadays, or that our problems are not real. They are different from our ancestors’, but of course we experience stress. It’s not only a matter of putting things into perspective. What’s bothering me, is that our stress response is out of sync: while our problems have become less life threatening, the health problems we encounter due to stress are becoming more serious. The more I read about it, the more I see the irony. 

Although I feel like a hungry bear on a daily basis, I cannot remember the last time I was nearly eaten by one. Still I often react like that’s the case, with all its consequences. And while I would love to get rid of that behavior, here comes the tricky part: when practicing mindfulness, it is not about eliminating things we don’t like. Nor about running away from them. That applies to stress as well. Mindfulness is about accepting what is, also when feeling pressured. So while our system prepares us for a fight or flight, we should choose neither. Just observe it and let it be. You might even feel better at once (although that’s not the purpose). No combat, no escape. Is that against nature? No. You know when you actually need to run. And you will. Something with a bear. And then basta.

Under pressure? Although mindfulness is not about resisting or avoiding stress, there are many benefits attributed to mindfulness when it comes to the reduction of stress levels. Frequent meditation reduces the activity in the “fight or flight”-center of your brain. It also helps in switching to your Being-mode (while your Doing-mode is associated with action and the stress response). Sounds good? Try one of the exercises I described in one of my previous blogs. But don’t expect a quick-fix. All in good time.