Loneliness is not only a sad place; it’s a bad place. Research has shown that lonely people die prematurely. The magnitude of the risk is considerable. It’s as bad as smoking! Loneliness impairs the immune system, triggers inflammation and disrupts sleep. If you’ve read my other blogs, you’ll know how inflammation increases the risk of heart disease, diabetes and cancer, and you’ll know that the quality of your sleep directly affects your BodyWHealth. More importantly, we know that it’s not enough to simply be with people; you can be lonely in a big city, or in a marriage. You have to be engaged with them to avoid unhealthy consequences.
To explain this we’ll need to learn a little about the human brain and its evolution. Hundreds of millions of years ago, our earliest ancestors had very simple brains. We will call these the “primitive” brain. Scientists also call it the “reptilian” brain, because it’s not a lot more than that, and if you picture the size of a snake’s head, you’ll guess that they have a tiny brain! This primitive brain did a great job helping its owner survive. But that’s all. It equipped the owner to fight or flight; its default mode is defense. Picture yourself in your most lonely, reactive, selfish, defensive state and you’ll understand what this brain is good at.
Happily, evolution added a second part to our mammalian brain in order to increase our reproductive success and survival. Hundreds of millions of years ago, we developed what I’ll call the “emotional” brain. Actually, it’s a collection of brain structures that we built around our primitive brain stem. Scientists also call this the “limbic” system. It acts as the emotional interpreter, and its currency is a neurotransmitter called serotonin, the “feel-good” chemical. The evolutionary purpose of our emotional brain is ingenious and our craving for serotonin transformed our existence in two dramatic ways. First, it turned us into loving parents. Reptiles (that only have the primitive brain) wastefully produce millions of offspring, hoping that a few will survive. We humans have one baby at a time (mostly) and efficiently invest our energy into the development of our progeny. Second, the lure of serotonin drove us to engage and collaborate with other humans, vastly increasing our survival success. Nature created serotonin as a pleasurable reward in order to reinforce social engagement.
Several things are known to stimulate an increase of serotonin in the emotional brain. Physical contact is the most important. When we snuggle together on a cold night (a good survival strategy for warm-blooded mammals), we are rewarded with a serotonin boost. Both affirmation and parenting behavior have also been shown to increase the “feel-good” neurotransmitter. Finally, we know that exercise and light increase serotonin levels. So, the arrival of the emotional brain and our strong craving for serotonin drive and reward affection and social engagement. We need these for BodyWHealth.
The emotional and primitive brains are both essential, and work together to make us human. They are the yin and yang, and balance each other. If we only had the primitive brain, we would be governed by fear and would live defensively. We often default to this mode under stress. The primitive brain is strong, but the emotional brain can override its influence. Serotonin switches off adrenalin and cortisol secretion, opposing our primitive fight and flight response, and enables us to control our selfish instincts. Note that we oppose fear with love. This is the fundamental antithesis that governs our lives. In essence, we need fear to survive; but to live, we need love!
The third component of the human brain is the cerebral cortex. This “cognitive” brain adds conscious thought and differentiates us from other mammals. It is the most recent evolutionary addition, and makes our brains three times larger than those of our closest living biological relatives. Unlike the primitive and emotional brains, we are in full control of the cognitive brain, and it can over-ride both. Thought is a powerful gift, and can influence the behavior of both our primitive and emotional brains.
The emotional brain, with its serotonin treasure, is sandwiched between the primitive brain and the cognitive brain. It is subject to the influence of both. The primitive brain exerts a negative, selfish pressure, insisting that we survive. The cognitive brain is under our active control and can influence our emotions either positively or negatively.
It’s clear that for BodyWHealth, we need our emotional brain overflowing with serotonin. Interactions with others drive this, but we know that people can be lonely in a marriage, and lonely in a city. So, clearly social interaction alone is not enough. We need social engagement. We need affirmation and physical contact. More powerfully still, we need to give. We must invest socially and emotionally. When we do this, we are rewarded with both serotonin and BodyWHealth.