So let’s get started with this topic! For many years we received the simple message that sun exposure is bad and causes cancer. We covered ourselves in sunscreen and thought little more of it. More recently, though, we are hearing about widespread vitamin D deficiencies and the benefits of getting regular sun exposure.
So how do we get it right to optimize our health?
To figure this out, first we are going to need to understand a little about the sun’s rays:
UV Radiation
UV radiation is part of the electromagnetic light spectrum that comes from the sun’s rays. The wavelengths differ in length, and are classified as UVA, UVB, and UVC.
UVC rays are the shortest, and mostly absorbed by the ozone layer before reaching earth.
Both UVA and UVB penetrate the atmosphere.
UVA are the longest waves of radiation and account for almost 95% of the UV radiation that reaches earth. They penetrate the deepest into the skin, including during the winter months and through glass panes, damaging collagen and DNA. They can cause wrinkling, loss of elasticity and pigmentation. Also, contrary to previous beliefs, we now know that UVA does also contribute to skin cancers.
UVA is the dominant tanning ray, and the one primarily used in tanning booths though in much higher doses than the sun. There are really no benefits to UVA exposure. It is best to avoid it as much as possible.
UVB rays are the rays we fear the most, as they cause sunburns and damage to the more superficial epidermal layers of the skin. They are linked to skin cancer. Because the earth’s atmosphere filters out much of the UVB rays, the intensity of UVB is highest in the middle of the day and during summer, but has the potential to burn all year round. UVB rays are also stronger the closer you are to the equator, at high altitudes and near reflective surfaces such as ice and snow. In contrast to UVA radiation, UVB does not significantly penetrate glass.
You might think that it would be best to completely avoid UVB rays too. Here’s the tricky part,
UVB rays are the only rays that help our body make vitamin D!
What does Vitamin D do for us?
Vitamin D is so important for our health because of its connection with a wide range of health issues:
- Reduces cancer risk.
- Helps us maintain healthy bones and teeth.
- Supports our immune system to fight infections, including colds and the flu.
- Supports cardiovascular health. Reducing incidence of hypertension, atherosclerotic heart disease, heart attack, and stroke.
- Helps with prevention of autoimmune diseases like multiple sclerosis or inflammatory bowel disease.
- Supports against vitamin D deficiency osteomalacia, which results in tiredness and achiness and can be misdiagnosed as fibromyalgia or chronic fatigue.
Working out how much sunshine is right for you.
Things to consider:
- You CANNOT make any vitamin D when you're exposed to sunlight through glass.
- UVA radiation is harsher in the morning, and late afternoon so, against our instincts, AVOID early morning and afternoon sun.
- You cannot make vitamin D until about 10am through until 3:00pm.
- ALWAYS keep your face protected because your face has a lot more sun exposure than any other part of your body and the skin of the face is more delicate.
- When you are trying to get sun exposure, uncover your arms and legs or more if that is available to you. The more skin that is exposed, the more vitamin D you can make.
- Fair skins need less sun than darker skins to make vitamin D.
To estimate how much sun you need:
- Estimate the time it would take you to burn in the middle of the day sun without sunscreen.
- In July and August go out in the sun for 25% of that estimated time 2 or 3 times a week.
- In March to June and Sept to October go out in the sun for 50% of that estimated time 2 or 3 times a week.
- Don’t try to get sun exposure November to February.
- If you stay out in the sun longer than you need to build up your vitamin D then cover up and wear a broad spectrum sunscreen for UVA and UVB protection.
Other ways to get vitamin D
If you can’t get enough sun to make the vitamin D you need, or if you know you are already deficient, you can ingest vitamin D by emphasizing fatty fish, pastured milk and eggs and mushrooms.
A vitamin D3 supplement can be beneficial, particularly to correct a deficiency. Ideally it should contain some of the cofactors for absorption. Here’s my favorite because it is so absorbable and bioavailable: nutraMetrix Isotonix Vitamin D3 with K2.
Look out for my blog next time where I’ll give nutrition tips to help you protect your body from sun damage from the inside!
As always, I’d love to hear your comments and please reach out if you need any help.