Vitamin D
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Most of us have heard the warning that too much sun exposure can be dangerous. Hi. I'm Bryan Yeaton and this is The Weather Notebook. As meteorologist Mish Michaels reports, there is a brighter side to those UV rays, one which will keep your bones healthy and strong.

In this day of heightened awareness, it almost seems sacrilegious to spend anytime catching rays. But, in fact, a little sun (fifteen minutes on a summer day) can do wonders for your bones. And here's why:

A good dose of those rays prompts the skin to produce Vitamin D which significantly boosts absorption of calcium in your bones. Without it, calcium would pass through your digestive system unused , leaving you body to steal calcium from the reserves in your bones. This can mean a loss of bone mass and lead to debilitating fractures.

The amount of D in our blood can vary based on the latitude of your location, the time of day, and the season of the year. In the summer, just going about your business-- with a casual exposure to the Sun, provides most of the D you need. Colder months are another story. Folks who live in northern latitudes, however, including cities like Boston, produce little D during the winter months. This D deficit lasts even longer just 10 degrees north in Edmonton, Canada, extending from October to March. During these low sun angle months, the body frees the D made during the summer from fat reservoirs to keep the bones happy. So, the prescription is fairly easy: a modest dose of sunny skies, please.

That's meteorologist Mish Michaels. The Weather Notebook is a production of the Mount Washington Observatory and supported by Subaru.