Getting your daily dose of sunshine is often recommended to boost your vitamin D levels. Unfortunately, if you have been heading outdoors with a layer of your trusty sunscreen slathered on, you may not be getting the full benefits of sunlight exposure.
Vitamin D is a vital nutrient for the body, needed to develop a strong musculo-skeletal structure and to avoid rickets, osteomalacia, and fractures. A deficiency of vitamin D has also been implicated in some cancers, type 2 diabetes, autoimmune disorders, Alzheimer’s disease, as well as cardiovascular disease.1 Dietary guidelines from the Institute of Medicine of the National Academies suggest about 600 IU daily for anyone under 70. 800 IU is suggested for those over 70 years.2
How Do You Get Your Vitamin D?
The primary source of vitamin D is skin photosynthesis.
Fatty fish and fish liver oils are a source of vitamin D, but most Americans get their dietary intake of the vitamin through fortified milk. Supplements offer another alternative route to get your vitamin D.4
Why Sunscreen May Not Always Be Good
Sunscreen is your first line of defense against skin damage. The American Academy of Dermatology recommends that everyone use a broad-spectrum sunscreen that protects against UVA and UVB rays. They suggest one with Sun Protection Factor (SPF) 30 or higher. However, they also mention that sunscreen use could cause the skin’s vitamin D production
One study on adults using sunscreen showed that in spite of sufficient sun exposure, they had low vitamin D levels in the body.6 And there are dozens more that echo the same findings.
Specifically, researchers have found that when a properly applied sunscreen with SPF30 is used, the skin’s loses its capacity to produce vitamin D. The decline is nearly 98 percent – which means virtually none is being produced. For SPF15 properly applied, the skin’s capacity for vitamin D production is reduced by 95 percent.7 8
With as many as 60 percent of all adults and about 40 percent of all children suffering from a vitamin D deficiency or insufficiency, this is now a widespread health concern.9
Alternatives To Traditional Sunscreen
One option is to skip the sunscreen for just that small 20–30 minute window midday when you get your sun exposure for vitamin D. The rest of the time, cover up and use sunscreen. But you do still expose yourself to the risks, albeit for a shorter window.
The American Academy of Dermatology suggests using vitamin D supplements to get in the requisite amount of vitamin D, rather than risk unprotected sun exposure.10