Have you had your vitamin D levels checked recently? I was shocked when my results came back as deficient. Deficient? How can that be? I live in sunny California! As we've become better at protecting our skin from harsh UV rays, our absorption of vitamin D through sun exposure has gone down. Luckily we can also get vitamin D in other ways, through the diet and supplementation if your doctor deems it necessary. Foods naturally high in vitamin D are fatty fish like salmon and tuna. Liver, cheese, egg yolks and surprisingly mushrooms, especially if grown under UV light, are good sources of vitamin D as well. Foods that have vitamin D added to it or are "fortified" such as milk, soymilk, almond milk, cereals, and some juices are also good sources. Read the nutrition facts label to make sure.
Why do we need vitamin D? Working hand-in-hand with calcium, vitamin D strengthens bones and protects against the loss of bone mass. This is especially important for growing children. Muscles require it for movement and nerves need it to carry messages between the brain and the body. Vitamin D can help the immune system fend off invading bacteria and viruses. More recent studies have linked low levels of vitamin D with depression. Seniors, breast-fed babies, and people with darker skin may need extra vitamin D but check with your health-care provider before supplementing.