Why do we need the sun?
We need it to synthesize vitamin D3. We get vitamin D3 mostly through the sun (and a small proportion through food).
What If We Don’t Get Enough?
Deficiency in vitamin D3 is associated with osteoporosis, heart disease, depression, autoimmune diseases, chronic fatigue, chronic pain, some cancers (17 types), rickets, diabetes, hypertension, neuromuscular disorders,…
Alternatively, too much exposure to the sun will lead to skin cancer. Yes. But the key word here is ‘too much exposure’.
What is Vitamin D3 Synthesis Exactly?
Before we get into what’s the right exposure, I’ll say a few words about how vitamin D3 synthesis works.
Vitamin D3 is made in the skin when the sun (more specifically the ultra-violet rays UVB) strikes bare skin.
The more bare flesh is exposed and the stronger the sun, the more vitamin D3 you’ll make. Sun protection cremes prevent vitamin D to be synthesized as they block UVB. Most sunbeds use UVA and not UVB. Hence, they will give you a tan but no vitamin D. Exposure behind windows does not count as windows block UVB. Finally, if you wash with soap after sun exposure, you’ll wash away most vitamin D before it has had the time to be absorbed.
Why It’s Important To Get The Right Sun Exposure
What happens next in your body explains why it’s important to get the right sun exposure.
After it’s been synthesized in the skin, vitamin D3 is transported to the liver where it is metabolized into calcidiol. Calcidiol goes to the kidney where it’s transformed into a steroid hormone (calcitriol). Calcitriol then circulates in your blood to regulate serum calcium. Calcium is vital to the function of the cells in the body, without enough calcitriol in the blood calcium levels will fall and illness will set in.
However, if your vitamin D tank is full, excess calcidiol does not go to the kidney but to every cell in the body capable of making calcitriol. And that’s when you get all the extra health benefits of vitamin D: strengthened bones, powerful immune system, healthy cardiovascular and heart function, risk limitation of many types of cancer (bladder, brain, breast, colorectal, eye, liver, lung,…), mood booster (less risk of depression and SAD),
That’s why, you do want your vitamin D tank full.
Unfortunately, we tend to stay indoors more and more and increased number of people are reported to have vitamin D deficiency. More than half the population in the UK and North-America would have insufficient levels of vitamin D! More than one in two!!! Chances are you might be one of them…
How Do I Make Sure I Get Just The Right Dose Of Sunshine … But Not Too Much?
Use common sense and adapt your sun exposure to where you live, the time of year, the darkness of your skin.
If you are fair-skinned, you’ll need less exposure to make vitamin D. If you’re dark-skinned, you’ll need more.
If you live in Northern latitudes (most of Europe, most of the USA), the rays of the sun are not powerful enough to generate vitamin D in the colder months (October to March).
The Vitamin D council (a non-profit educational corporation) recommends 20 to 30 minutes (for fair skins, up to 6 times longer for dark skins) of exposure a day: from April to September, in midday sun, showing as much flesh as you can, not wearing any sun protection. Only wash the exposed areas with water afterwards (no soap).
Only expose yourself until your skin turns pink (not red). Do not get sunburned.
In the winter months, get your vitamin D through food to compensate. Good sources are: oily fish (such as salmon) and eggs. Use a sunbed (with UVB!) if you can.
In conclusion, don’t be scared of the sun. Stock up on sun in the spring and summer months.
Be careful not to burn.
The sun is free. It’s good for you.
Let it shine!!!