Vitamin D is critical for bone health and also plays a role in immunity. But many US infants and toddlers aren't getting enough vitamin D. According to research from the Children's Hospital in Boston, a full 40% aren't getting the appropriate amount of vitamin D.

Breast milk doesn't contain high quantities of vitamin D, so if you're breastfeeding your infant ask your doctor if supplementing the vitamin is a good idea. Toddlers can benefit from vitamin D-fortified milk. Perhaps the best source of vitamin D is sunlight. While it's, of course, important to protect your child's skin, some exposure to sunlight is healthful as it triggers the production of vitamin D in the body.

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I've mused on the subject of sunlight exposure a few times in the past, and how I've read (and experienced) that sunlight can make you feel refreshed and alive after as little as 10 minutes of exposure per day.

The main reason, from the research I've done, is that sunlight stimulates a large production of Vitamin D naturally within one's body. New research says that, combined with an intake of Vitamin K, can decrease a person's risk of contracting breast cancer by 50% -- and of contracting colorectal cancer by more than 65%.

If those aren't two more good reasons to get a decent dose (when practical) of sunlight per day, I am not sure what is. After all, most of us spend more time inside these days -- but it's good to get out and smell the roses -- while getting some sun.

[Edited: corrections]

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