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Can Working Indoors Give You Skin Cancer?

working indoorsMany skin cancer screenings are held during May, which is Melanoma/Skin Cancer Detection and Prevention month. To find a free skin cancer screening in your area, you can click on the link below. You should note that skin cancer screenings tend to be rapid and are not a substitute for a full skin examination by your own dermatologist or physician.

This makes May a good time to spread the word that, despite the persistent myth, healthy UVB exposure is not the cause of melanoma.

This is why an epidemic of melanoma has broken out among indoor workers. In fact, indoor workers get three to nine times LESS solar UV exposure than outdoor workers get, yet only indoor workers have increasing rates of melanoma -- and the rates have been increasing since before 1940.

In fact, UVB light, which causes your skin to produce vitamin D, is protective against cancer.



Vitamin D Dose Recommendations
Age Dosage
Below 5 35 units per pound per day
Age 5 - 10 2500 units
Age 18 - 30 5000 units
Pregnant Women 5000 units
There is no way to know if the above recommendations are correct. The ONLY way to know is to test your blood. You might need 4-5 times the amount recommended above. Ideally your blood level of 25 OH D should be 60ng/ml.
Dr. Mercola's Comments:
Since May is Melanoma/Skin Cancer Detection and Prevention month, I thought it would be fitting to bust some of the prevalent myths surrounding this disease.

Contrary to what you may have heard, appropriate sun exposure actually helps prevent the fatal type of skin cancer, melanoma. In fact, melanoma, has been found to decrease with greater sun exposure, and can be increased by sunscreens.

One such study discovered that melanoma patients with higher levels of sun exposure were less likely to die than other melanoma patients, and patients who already had melanoma and got a lot of sun exposure were prone to a less aggressive tumor type.

While public health officials have been warning that exposure to ultraviolet (UV) radiation from the sun increases your risk of developing melanoma, an epidemic of the disease has broken out among indoor workers.

These workers get three to nine times LESS solar UV exposure than outdoor workers get, yet only indoor workers have increasing rates of melanoma -- and the rates have been increasing since before 1940.

Why Would Indoor Workers Have Higher Rates of Melanoma?

There are two major factors that help explain this, and the first has to do with the type of UV exposure. There are two primary types of UV rays from sunlight, the vitamin-D-producing UVB rays and the skin-damaging UVA light.

Both UVA and UVB can cause tanning and burning, although UVB does so far more rapidly. UVA, however, penetrates your skin more deeply than UVB, and may be a much more important factor in photoaging, wrinkles and skin cancers.

A recent study found that indoor workers may have increased rates of melanoma because they’re exposed to sunlight through windows, and only UVA light, unlike UVB, can pass through window glass.

At the same time, these indoor workers are missing out on exposure to the beneficial UVB rays, and have lower levels of vitamin D.

As you probably know by now, vitamin D is formed in your skin from exposure to sunlight. The sun, in turn, does increase genetic damage in your skin and can cause skin cancer, but nature has designed a clever system to help prevent this risk.

Dr. John Cannell, one of the leading authorities on vitamin D and founder and executive director of the Vitamin D Council, does an excellent job of explaining the system in this video but to give you a summary, when vitamin D is produced in your skin, it goes directly to the genes in your skin where it helps prevent the types of abnormalities that ultraviolet light causes.

Hence, when you avoid the sun entirely, or slather on sun block whenever you go out, your skin is not making any vitamin D, and you’re left without this built-in cancer protection.

So it’s the combination of exposure to UVA light and lower vitamin D levels that appears to be causing the increased rates of melanoma, and the indoor workers could clearly benefit from spending some time outdoors in the sun.

How to Get the Benefits of Vitamin D With Little Risk of Skin Cancer

Aside from protecting your skin from sun damage, optimizing your vitamin D levels can help you to prevent as many as 16 different types of cancer along with many other diseases as discussed in this past article, Vitamin D -- The Master Key to Optimal Health.

It’s absolutely tragic that dermatologists and sunscreen manufacturers have done such a thorough job of scaring people out of the sun -- your optimal source for natural vitamin D -- because it’s simply essential for your health.

If you want to get out in the sun to maximize your vitamin D production, and minimize your risk of malignant melanoma, the middle of the day (roughly between 10:00am and 2:00pm) is the best and safest time to go.

During this time you need the shortest exposure time to produce vitamin D because UVB rays are most intense at this time. Plus, when the sun goes down toward the horizon, the UVB is filtered out much more than the dangerous UVA.

You just need to be cautious about the length of your exposure. You only need enough exposure to have your skin turn the lightest shade of pink. This may only be a few minutes for some if you have a very pale skin.

Once you reach this point your body will not make any additional vitamin D and any additional exposure will only cause harm and damage to your skin.

Most people with fair skin will max out their vitamin D production in just 10-20 minutes, or, again, when your skin starts turning the lightest shade of pink. Some will need less, others more. The darker your skin, the longer exposure you will need to optimize your vitamin D production.

To learn more about sunlight and vitamin D, including why I recommend getting your levels tested and how to use the sun for cancer prevention, please set aside an hour to watch my free lecture on vitamin D.

And remember, spending some smart time out in the sun will optimize levels of one of your body’s natural defenses against cancer, vitamin D.