Too Much? Too Little? How Much Sun SHOULD We Be Getting?
Flowers poking through the waning snow. Things become green again. Windows open up, circulating fresh air. Days become longer and we see more sunlight. Ahh... the wonderful, bright, warm sun! When it comes to appropriate exposure, the medical field has had a mixed relationship with our sun, however.
What ISthe optimal, healthy amount of sun exposure that we should be getting?
In my career as a doctor, I have seen recommendations regarding sun exposure swing back and forth like a pendulum. I've heard many recommendations:
"Get out of the sun! You'll get skin cancer."
"Get more sun, it will help your mood in the winter months."
"Your vitamin D level is low, you probably aren't getting enough sun."
These mixed messages leave people bewildered. Let's look a bit more in-depth about the pros and cons of sun exposure.
Benefits: Improved Mood
Lack of sunlight exposure has been shown to be the causal factor in Seasonal Affective Disorder (SAD). During the winter months, opportunities wan for exposure to the sun, especially in day shift workers who spend their time indoors. I can vouch that here in Michigan I walk into and out of work in darkness during the mid-winter months - it's depressing! Studies have shown that the recommended exposure to improve/maintain mood is around 30 minutes per day. For more information on SAD, see my past blog. As an alternative, natural sunlight lamps can be purchased to give this daily dose.
Benefits: Vitamin D
Over the past few years, much attention has been given to vitamin D deficiency. Having weathered the failed promises of vitamin E supplementation, I was skeptical. However. after finding shockingly low vitamin D levels and seeing huge improvements in mood and body aches, my views have changed. Data further supports that adequate vitamin D stores prevents future fractures from osteoporosis.
How does the sun play in here? We take in dietary vitamin D from a number of food sources in its inactive form. Sunlight exposure on the skin activates the vitamin D to the form which is utilized by the body. Studies show that it takes approximately 15 minutes of sun exposure to significant amount of our body (face and arms) each day to convert an adequate amount of vitamin D. Keep in mind that sunscreen on the skin blocks this conversion. As an alternative to sun exposure, the metabolized version of vitamin D can be taken as a pill (1000-2000 international units per day).
Harm: Skin Cancer
Basically, increased skin exposure to sunlight means increased risk of skin cancer. Skin cancer can strike anyone, but lighter-skinned persons are more susceptible to cancer. There is no "safe" amount of exposure, but preventing burns reduces risk. This can be accomplished by avoiding the sun, wearing protective clothing, or using sunscreen. While more of a vanity issue than a health hazard, years of sun exposure can break down collagen in the skin and promote the development of wrinkles.
All things considered, some sun (but not too much) is optimal. Getting that 15-30 minutes of skin exposure per day seems go give the benefits at minimal risk. Beyond that, protective measures are recommended.
Have a fun and safe spring and summer!