Nowadays, you hear a lot of people make the claim that neither food nor exercise are very important compared to your light environment. They suggest that if you’re living under artificial lighting all day and all night, all the exercise and good food in the world won’t make you any healthier. They say that if you are not getting sun during the day, during the sunrise and sunset, and feasting on the full range of wavelengths provided by the sun, and all its glory, that you might as well not even think about food or exercise until you fix your light exposure.

I’m a guy who’s been talking about artificial light and sun exposure for well over a decade. I’ve written about it in my books and on my blog, and I’ve always been a sun fan from my childhood in Maine, where sun was scarce, to my teenage years in Florida, where it was plentiful, all the way through my time in California, where one of the reasons I moved to Malibu was specifically to get as much sun and beach as possible. And now I'm in Miami, one of the sunniest places in the country.

I’m no stranger to the merits of sun exposure and natural light. I’ve also been writing about the dangers of artificial light. So when I say what I’m going to say, realize that I’m not throwing out the baby with the bathwater: light environment is extremely important, and I’ve always said that.

However, I think it’s pretty clear that movement is a huge issue in most people's lives. Movement comes first before anything because way back in the beginning, in the deep dark oceans of our archaic past, movement is what those organisms did. Voluntary, autonomous movement is what sets animals apart from plants: our ability to fly, swim, slither, walk, crawl, or leap from point A to point B in pursuit of food and light.

What is one of the best predictors of longevity in older people? Walking speed. You get a group of senior citizens, tell them to walk around the block at their normal pace, and time them; all else being equal, the ones who walk at a faster pace will live longer than those who walk more slowly. Another one is grip strength. Having a strong handshake is another predictor of long life; that is movement, that is one’s ability to generate force and impress oneself upon the world.

What about food? Ten years ago I would have said food was the most important. I'd come from a place of being a marathoner, hanging out with other marathoners, and then I was an Ironman hanging out with other Ironmen. And then I was a trainer who trained elite athletes. My entire life I’ve been surrounded by and immersed in the world of physical culture. Movement was simply a part of the fabric of life, something you couldn’t avoid. The food environment changed more drastically than the exercise environment. Up until maybe the '90s or early 2000s, pretty much everybody got a lot of physical activity, especially children. You went outside and played with friends, you roamed the streets, you probably logged 30 to 40,000 steps on an average afternoon. But the food was changing, and the food was arguably a bigger issue than movement for most people. For me, changing my food seemed to have the most immediate impact.

Now I know that food and movement are inseparable. That it's not a matter of picking just one. You not only can address it all—you must address it all.

I have no doubt that a lot of the studies never control for light exposure. And light exposure, sun exposure, and all those things will undoubtedly play a role in a person's health and mortality risk. But you simply cannot turn into a plant and just sit there focusing on your light environment; you are more than that. You contain multitudes, and you require a multitude of inputs in order to be truly healthy, vibrant, and powerful. We aren't going to photosynthesize our way out of this health crisis.

What do you think, folks? What's most important to your health—food, movement, or light? Let me know on our latest Instagram post.