Primal Blueprint Law 8: Get Plenty of Sunlight
Primal Blueprint Law #8 is “Get Plenty of Sunlight,” and it might be one of the most important ones. After all, perhaps the biggest change to the human environment has been a switch from outdoor living to indoor living. We went from working, playing, and hunting outside in the elements to doing all those things inside buildings. We sheltered in open-air structures, caves, lean-tos, and huts.
Even when we were inside, we were half outside. We sheltered in open-air structures, caves, lean-tos, and huts. We weren’t sealed up surrounded by impermeable climate-controlled walls, roofs, and windows. The air flowed, the sunlight streamed in, and there wasn’t such a big difference between being inside and out.
Benefits of Sun Exposure
The sun offers many vital health benefits:
It maintains our circadian rhythm by which every cell and organ of our body operates. If we don’t get sun exposure throughout the morning, noon, and afternoon, our circadian rhythm goes haywire and things don’t work correctly.
It helps us get to sleep at night. Sun in the day, darkness at night sets the physiological pathways that enable good sleep.
It provides vitamin D. When sunlight strikes our skin, the cholesterol contained there converts to vitamin D—an important compound controlling immunity, sex hormones, bone formation and density, cognitive function, and physical performance. Vitamin D is closer to a hormone than a vitamin.
It improves endothelial function. Sunlight hitting the skin also triggers the production of nitric oxide, a compound that improves blood flow and helps the heart pump nutrients and oxygen to the tissues that need them.
It improves mood. We have endogenous opioid systems that exposure to sunlight triggers. Sunlight literally gets us high.
It improves eyesight. Kids who spend too much time indoors are at a greater risk of myopia. True sun exposure appears to improve eyesight. Note: this doesn’t mean staring into the sun.
Getting Sun Safely
It’s true that you have to expose yourself to the sun safely. You still can burn, and if you burn often and badly enough, you can get skin cancer.
To do it safely:
Get morning sunlight. The infrared light present at sunrise primes your skin for greater resistance to UV damage when stronger sun arrives later in the day.
Build your solar callus slowly. Get as much sun as you can tolerate without burning, then get under shade. Eventually, you’ll be able to add more and more sun as your tolerance increases. Building the solar callus should start in late Fall, or whenever the sun reappears.
Avoid burning. This goes without saying but I’ll still say it. Burning is bad.
Wear clothing, use shade, and use high-quality mineral sunblock (containing zinc oxide or titanium dioxide) when necessary.
Today we spend 8 hours a day sealed up in impermeable climate-controlled offices surrounded by walls and roofs. If we even see the sun it’s through a window, which filters out many of the beneficial wavelengths of sunlight. That has to change.
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* This blog reflects my personal views and opinions and isn’t intended as medical advice, but I hope it will be informative and inspiring as you pursue a healthy, fulfilling life.



