The People's Perspective on Medicine

Will Using Sunscreen Lead to Vitamin D Deficiency?

Sunscreen blocks vitamin D formation in the skin, but proper use provides skin protection from sunburn and still allows for some vitamin D manufacture.

Sunscreens are big business. Americans spend well over $8 billion a year slathering on creams, lotions and gels to protect themselves from sunburns.

People have gotten the message that exposure to the sun’s ultraviolet radiation equals aging, wrinkling and skin cancer as well as sunburn. But they have also been told that vitamin D, made in the skin from sun exposure, is vital for good health.

Mixed Messages

These messages are contradictory. That’s because properly applied sunscreens prevent the formation of vitamin D3 as well as sunburn and skin damage (Advances in Experimental Medicine and Biology, 2014, vol. 810).  That leaves us with a dilemma: How do you get enough sun to make vitamin D but not so much that you damage your skin? The answer is complicated, because the amount of sun exposure required varies depending on the time of year, the geographical location, the color of the skin and the time of day.

Obviously, the sun is strongest in summertime in the middle of the day. In a sunny place like Phoenix, Arizona, or Tampa, Florida, just about six minutes of sun exposure midday offers enough ultraviolet (UV) for fair skin to make 1,000 IU of vitamin D. Dark brown skin requires more exposure, up to 15 minutes, to make the same amount of vitamin D.

Further north, in Madison, Wisconsin, or Boston, Massachusetts, someone with fair skin might need an hour of sunshine on bare skin, even midday in the summer, to make that much vitamin D. Dark-skinned folks would need twice that much time. In the winter, even if someone were brave or foolish enough to go outside in shorts and short sleeves, the sun is not strong enough for anyone to make much vitamin D.

Take Advantage of Summer Sun

Ideally, then, a person would take advantage of summer sunshine to get 15 or 20 minutes of sun without sunscreen several times a week. After that, slather on the sunscreen and pull on the long sleeves and the hat.

Finding the Best Sunscreen

How do you make an informed decision about your sunscreen? It is important to select a product that protects against UVA as well as UVB radiation. Look for a product that declares “Broad Spectrum” right on the front label. It should have an SPF (Sun Protection Factor) of at least 15.

Scoping Out SPF

Higher SPF sunscreens provide better protection, up to a point. FDA will be limiting companies from claiming SPF values above 50, since there doesn’t appear to be data showing a reliable difference between an SPF of 50 and one of 75 or 100.

Skip the spray: consumer groups such as the Environmental Working Group (EWG) and Consumer Reports say it is difficult to apply an aerosol sunscreen thickly enough and to keep it out of eyes and lungs while applying it.

Put On Enough

Applying enough sunscreen is an important consideration. Many people skimp on the amount they smear over their skin. That significantly reduces the protection a sunscreen can offer. It is also important to re-apply it after getting out of the water or sweating.

Sunscreen Worries

Some of the ingredients in sunscreens, particularly oxybenzone and octinoxate, can act like hormones in human tissues. It would be smart to avoid such endocrine disruptors. EWG lists sunscreens that don’t contain hormone-disrupting chemicals on its website: Consumer Reports has also published its 2015 sunscreen reviews online for subscribers.

Rate this article
4.7- 21 ratings
About the Author
Joe Graedon is a pharmacologist who has dedicated his career to making drug information understandable to consumers. His best-selling book, The People’s Pharmacy, was published in 1976 and led to a syndicated newspaper column, syndicated public radio show and web site. In 2006, Long Island University awarded him an honorary doctorate as “one of the country's leading drug experts for the consumer.” .
Skin Care and Treatment

Download home remedies and medicines for acne and excessive sweating. Oxybenzone-free sunscreens. Coping with dry skin, eczema, wrinkles and psoriasis. Inexpensive barnyard beauty aids.

Skin Care and Treatment
Join over 150,000 Subscribers at The People's Pharmacy

We're empowering you to make wise decisions about your own health, by providing you with essential health information about both medical and alternative treatment options.

Showing 6 comments
Add your comment

Am I correct that, during the 10 to 20 minutes a person is in sun for Vit D, that there should be sunscreen on the face, because that skin is often the most sun sensitive.
Thank you.

If I use an SPF of 75 and apply it thinly, will it work as well as SPF 30? I wonder because a thin layer of sunscreen feels better on my skin than the thick recommended layer.

The recommendation is to use a lower SPF–at least 15 but not necessarily higher than 30–and apply it at a reasonable thickness, as recommended.

I clicked on the Consumer Reports site in your article above. Consumer reports will not give you sunscreen ratings unless you subscribe to them.

I do my best to avoid the sun and wear sunscreen on exposed skin 365 days a year because I have a history of melanoma (caught early). For me, I’d rather take D3 supplements than risk a recurrence, and cumulative exposure to the sun over a lifetime is one risk factor I’ve tried to minimize since I was diagnosed 10 years ago.

I have been using sunscreen for years.. sensitive kind and sometimes the one for babies. I found the had the same ingredients. My dermatologist told me to use it all year long. I, however, do take D3 for my bones.

I watched some drs show last year. They said some ingredients would affect the thyroid gland. I think it was the ingredient hex something.. most sunscreens have that ingredient.

* Be nice, and don't over share. View comment policy^