Tucson is heating up with this slew of 100-degree days and everyone is trying to stay out of the sun—but is that a good thing? Doctors and researchers have been touting the benefits of vitamin D, and the word on the sunny side of the street is that the most natural way to boost your D levels is to soak up some sun. So should you subject yourself to some outdoor time in the heat of summer, or bask in air-conditioning and stick to vitamin pills and supplements? Let’s take a look at the facts.
Vitamin D by the Numbers
Vitamin D is called the “sunshine vitamin,” because it’s not just a vitamin; it’s a hormone that our bodies make from a multi-step process that starts with exposing our skin to the UVB rays of the sun.
Recent research has linked vitamin D to lowered risk of cancer, heart disease, stroke, diabetes and more—in addition to its known benefits for bone health when combined with calcium. The problem is that up to 75 percent of us seem to have a deficiency in this valuable vitamin.
As of 2010, the recommended daily allowance (RDA) of vitamin D is 600 IUs (international units) for people age 1 through 70, and 800 IUs for adults better than 70. These amounts are calculated as being enough to keep our bones strong and reap the benefits above. And in theory, we can get more than these amounts just by getting some sun. Some research indicates that five to 30 minutes of midday sunshine on your unprotected skin—specifically, your face, arms, legs, or back—two to three days a week will give you all the vitamin D you need and more. So, if you spend time outdoors, without a UVB-protecting sunscreen, you should get the recommended amount of vitamin D, right?
Not necessarily. Multiple factors can slow or prohibit the vitamin D production mentioned above—like dark skin pigmentation, high levels of air pollution, and even being overweight.
Still not convinced? If you are a true “sunbird” who soaks up the sun’s rays with the excuse that you’re soaking in some vitamin D, here’s one more fact: Even though you live in sunny Arizona, you’re still not far enough south to get enough UVB exposure to naturally produce enough vitamin D through sun exposure.
Sun and Older Skin
Skin damage from overexposure to the sun accumulates over your life; those childhood sunburns, tanning by the pool, and working outdoors can add up to a late-in-life skin cancer. And just because you are no longer spending hours poolside, your skin is still vulnerable—in fact, it is more vulnerable if you’re over 70. According to a 2009 study by University College London, older adults carry a greater risk of skin cancers because older skin has lost the ability to mobilize the immune system to ward off cancers and infections.
But what about increasing my vitamin D levels, you may ask? Stick to getting D from food and supplements. Although vitamin D does not naturally appear in many foods, a surprising amount of dairy products and other foods have been fortified for years. For example, in the 1930s, milk manufacturers in the United States and Europe began fortifying all cow’s milk with 100 IU of vitamin D per cup (originally to eradicate rickets). Yogurt, breakfast cereals and orange juice are also routinely fortified—specifically to help you get the vitamins you need.
So get out your floppy hat, your broad-spectrum sunscreen, and your vitamin D-fortified foods, and get ready to enjoy summer in Tucson. Just be sure you Age Well in the shade.