Whenever anyone makes a claim, ALWAYS ask if it makes sense from an evolutionary perspective.

Most living things time their days with an internal clock that is synchronized by external cues (e.g., light and dark cycles). The sun is one constant that has been around forever, therefore our circadian rhythms developed to coincide with these light and dark cycles. This means that our biology is a product of the cyclical nature of the sun. This is evidenced by the light-sensitive receptors built into the cells of our eyes, skin, blood, and bones. 

Why should you care?

Well, because our biology is indelibly linked to the sun, it would also be fair to reason that it plays a role in our health as well. And that’s the point I am trying to get across here.

Before industrialized society, we had always been at the whim of the natural environment. Shifts in orbit and the earths rotation around the sun provided consistent cyclical change that forced us to endure challenges that come with the differing seasons. We had always “feasted” in the summertime to endure the “famine” that always followed in the winter. Our body instinctually knows that the long days of summer are going to be followed by the cold days of winter, and that means less access to food. Summertime means carbs are plentiful, as they literally grow on trees. Our body craves them so we can store fat to keep us alive for the impending winter when food is scarce. 

Here’s a simplistic view of how it works:

1. ‎Long hours of light signal summertime.
2. ‎Summertime means carbohydrates are plentiful and can be eaten to excess.
3. ‎Eaten to excess causes accumulation of fat (and interestingly, lowers the freezing temperature of cellular structures to make us more robust to colder weather) so that we can survive the winter.

Interesting aside: Most disease processes of modernity can be seen as adaptive mechanisms for the body to prepare itself for a shift in the environment. For example; Type 2 Diabetes can be seen as a survival mechanism, but in a world where winter never comes, it becomes a “disease.” The never-ending artificial light cycle, coupled with the temperature controlled environment we live in, exacerbated by high levels of chronic stress jacks up our hormonal cascade and registers as long days of summer signaling us to eat more for a winter that never comes. 

In the context of modernity, the effects of constant stress and artificial light added up pretty quickly. We live in a fear-based 24-hour news cycle that creates an environment where we live under constant threats of war, rape, disease, depression and getting fat. This stress is heralded by cortisol which drives us to consume carbohydrates so we can attempt to reach homeostasis by balancing our cortisol with the insulin response. All the while, our circadian rhythmicity becomes disrupted because we’re staring at blue-lit screens all day, telling our brain that it’s daytime, signaling the long days of summer. And because summer comes before winter, our body “knows” we need to eat so that we can have enough stored energy to survive the winter. BUT, WINTER NEVER COMES because everything in our environment is signaling that it is summertime and we need to eat.

While living in endless summer may seem like a great thing in theory, it completely throws off our biology. There is no day without night, there is no ying without yang. And there should be no summer without a winter. Life is about balance, without it comes the real pandemic of “dis-ease.”