You may have heard the buzz about vitamin D deficiency over the past several years. Because of years of sun-phobia and overuse of sunscreens, largely due to worry over skin cancer, as well as improper diet and compromised overall health, collective Vitamin D levels are much lower than they should be. In fact, over 70% of US children suffer from insufficient or deficient vitamin D levels (source).
Why does this matter? Vitamin D is necessary for a multitude of functions in our body, some of which are only beginning to be understood by science.
Once thought to only be of importance for bone health, it now seems Vitamin D plays a role in everything from muscle function, our immune system, brain, and cardiovascular health, to reproductive health and our mood.
There is even quite a bit of evidence that proper Vitamin D levels actually protect us from skin cancer!
Now a note about skin cancer.
I know many people who have either personally been affected or know someone who has been affected by skin cancer. Skin cancer is serious and I am certainly not advocating for unsafe, long-term sun exposure that causes sunburns.
It is sunburn, not safe and responsible sun exposure, that contributes to skin cancer.
We are definitely talking about safe sun exposure that allows our body to absorb and manufacture Vitamin D to promote our overall health.
So does any and all sun exposure allow your body to get Vitamin D?
It turns out that, no, there are only certain times per year, depending upon where you live, that you can actually get Vitamin D from the sun.
The sun has to be at the correct angle in the sky and you need to go outside at the right time of day to be able to take advantage of the UVB (not UVA) rays. This is one reason some people experience mood changes during the darker, winter months, in northern latitudes, along with compromised immune systems (hello, winter colds!) when their Vitamin D levels drop - they simply can't get optimal sun exposure for their latitude.
How to Get Vitamin D from the Sun
Depending on the sun for our Vitamin D is the smartest, easiest, and least expensive option.
The lighter your skin, the less time you need in the sun - as little as 10-15 minutes in the midday sun, exposing as much skin as possible (your back, abdomen, or legs absorbs faster than just your face and arms, for example), while darker skins need longer - up to 2 hours in some cases - to produce the same amount.
You want to aim for exposure for about half the time your skin would need to turn pink, or tan, and certainly not long enough to burn.
The further away from the equator you live, the less time of the year you can actually experience UVB rays. Pollution, cloudy days, and getting sun through glass also drastically reduce your availability to absorb UVB rays.
What's the best time to get sun?
In order for your skin to produce Vitamin D from sunshine, you need exposure to UVB rays, which are only available when the sun is above an angle of about 50° from the horizon. When the sun is lower than 50°, UVB rays are reflected and only UVA (the more damaging type of ray implicated in skin cancer) gets through.
Check out this calendar to find the best times and days of the year in your location when the sun is above 50 degrees from the horizon. This video explains how to do this in detail, as it can be a bit tricky to understand the timetable.
Generally, midday, on clear sunny days, between 10 am-2 pm, during the late spring, summer and early fall months are appropriate for much of North America. In the north, no matter what time of day you go out during the winter, you will not be able to access UVB rays.
To additionally boost your absorption of Vitamin D, avoid showering directly before or after sun exposure- and if you must shower, minimize the use of soap (that is, don't lather all over the body). You don't have to go crazy with this, but even allowing a few hours after sun exposure before showering (again, mainly with soap) can possibly allow you to absorb more Vitamin D.
Getting Vitamin D from Food
We aren't able to absorb all the Vitamin D we need from food, and though we can supplement with Vitamin D3 (make sure to get a blood test for your Vitamin D [25(OH)D] levels before implementing heavy or prolonged supplementation), some people do not tolerate or respond to supplements the same way they do to the sun.
The conversion of Vitamin D in our bodies involves many co-factors and depends upon a healthy gut, liver, and kidneys as well.
Real food sources containing Vitamin D would be cod liver oil, fatty fish, oysters, beef liver, and egg yolks. Fortified processed foods do not contain the right form of Vitamin D (D2 instead of the correct D3) and are not real food diet-friendly.
Vitamin D aside, a wholesome and nutrient-dense diet rich in healthy fats and antioxidants like lycopene and astaxanthin can play a big role in sun protection.
