Let’s talk about the Sun. The fiery star 93 million miles away that enables life on Earth. The keeper of the light, marking the start and end of our days. The universal symbol of ultimate power and glory. The object of one of my favorite poolside pastimes: sun-napping.

But the Sun also has haters.

Mixed messages have been fed to people over the last 30 years about the dangers and benefits of the Sun. We can’t live without it, but apparently, according to some, we shouldn’t directly expose our skin to it. Does that make sense to you?

It doesn’t make sense to me. At all.

I know, skin cancer this, melanoma that. It’s a real thing. Just like over-eating, over-exercising, and over-sleeping are real things. Too much of any good thing makes it TOO MUCH OF A GOOD THING.

The power of sunscreen was first revealed to me during a neat little experiment in a high school science class. We were given beads that changed colors when exposed to the sun. Outside of the classroom (oh, the Sun!) we placed one bead in direct sunlight where it changed from yellowy white to soft pink. Another bead was placed under a transparent piece of overhead projector plastic that had been smeared with sunscreen. Lo and behold, that bead did not change colors. Pretty compelling proof of the power of sunscreen.

I also remember the science teacher, who looked pallid and sickly, preaching about the dangers of the Sun and how we should stay out of it at all costs. I can’t say I was convinced of this advice even at the time and, over the years, have learned that scientifically my science teacher was wrong.


It is a fact that unfiltered sunlight contains life-sustaining Ultraviolet B (UVB) rays which our bodies use to create Vitamin D3.

Here’s how it works: Our skin contains a form of cholesterol that absorbs the UVB. The cholesterol+UVB chemically converts into the pre-vitamin form of D3. This pre-D3 hops a ride on the bloodstream down to the liver, where it gets converted to yet another form of D. This gets passed along to the kidneys, which do the finally processing into the form of Vitamin D3 that our bodies require.

I explain all that to reinforce that our human bodies were designed for sun exposure. Vitamin D is one of the few vitamins that we don’t get an adequate amount of through nutrition alone. Fatty fish, eggs, and fortified foods contain Vitamin D, but the levels are miniscule by comparison and need to be supplemented. Yes, the Vitamin D3 capsule or liquid supplements we take are useful for this purpose, especially in winter time. However, many people don’t absorb supplemented Vitamin D3 well or at all, making it a questionable choice when a natural source is right outside the door.


There’s been news lately of a Vitamin D epidemic whereby perhaps 90% of the U.S. population is deficient. A big reason for this is the amount of time we spend indoors at our jobs. Symptoms of Vitamin D deficiency include:

  • Weakness
  • Chronic fatigue
  • Depression
  • Trouble sleeping
  • Anxiety
  • Weak or broken bones
  • Weakened immune system
  • Inflammation and swelling

Think about the ailments on that list. Most are things that affect me, you, and most everyone around us. Could it be true that we are chronically Vitamin D deficient?


In contrast, the benefits of sufficient levels of Vitamin D include disease prevention and promotion of optimal wellness. Vitamin D:

  • Is key to building strong bones by increasing absorption of calcium and phosphorous
  • Reduces diabetes risk by reducing insulin resistance
  • Reduces risk of heart disease by lowering blood pressure, improving arterial elasticity, and improves glycemic control
  • Reduces risks of various cancers by inhibiting cancer cell growth, increasing cell differentiation and reducing metastasis.
  • Prevents and reduces symptoms of depression
  • Probably aids in reducing whole-body inflammation, which is the source or symptom of many underlying conditions


How much sun exposure you need depends on where you live, time of year, time of day, your natural skin tone, and your age. As sunlight travels through the atmosphere, UVB gets filtered out. Where you live relative to the equator dictates the directness of the UVB rays. Similarly, time of year alters the angle of regions of the earth relative to the sun. On a micro level, because the sun is further away in the morning and evening, UVB is heavily filtered as compared to the directness of the noon-day sun.

I found a cool graphic from Mercola that shows likelihood of Vitamin D synthesis by your body at different times of year:

One more thing: UVB rays don’t penetrate clouds or pollution. But UVA does—meaning your skin can still burn when cloudy without ever receiving the beneficial UVB.

Your skin tone will also determine how much direct sunlight you need on a daily basis. Lighter skinned people require less and darker skinned require more. This is because the pigmentation in skin, coming from melanin, filters out the UVB.

Your age is key to Vitamin D generation. A person in their 20s produces 4x as much as a person in their 60s.

Due to the complexity of atmospheric filtering and skin pigmentation, it’s difficult to nail down exactly how much time you need to spend in the sun. If you’re targeting a healthy 10,000 IU of Vitamin D3 per day1, then exposure could be as little as 15 minutes or as much as a few hours.

The best information I found is a rule of thumb that says to get half the sun exposure it takes for your skin to begin to burn to get your vitamin D and expose as much skin as possible. So if I know that in May I will burn in 30 mins, 15 minutes is adequate. But when I’m all nice and tan in August, it might take four hours. And I’ll get way more Vitamin D synthesis happening in a bikini than in a T-shirt and booty shorts.

Here’s something I bet you never heard before: If you bathe using soap too soon after sun exposure, you can actually wash away the Vitamin D being produced by the skin. Apparently water contact isn’t the issue—meaning you can feel free to swim and produce Vitamin D all you want—it’s the soap. Vitamin D penetration into your bloodstream can take up to 48 hours, but please don’t go that long before you bathe!


Humans were made with the requirement to get our Vitamin D3 through sun exposure. It’s not natural or healthy to sit indoors all day—and we all know it. So let’s get outside sans sunscreen (for a least a few minutes!) and soak up the sun!

1 Traditional researchers say that <4,000 IU of daily Vitamin D is adequate and any more should be considered an overdose. They base these levels on Vitamin D’s benefit being for bone health, without consideration toward the many other diseases and symptoms that seem to be impacted by increased levels. I lean toward alternative sources that follow cutting edge and natural treatments for disease which generally recommend higher doses.


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