Recharge Your Body's Defense System

Your immune system serves as the body’s guard force: it fights off dangerous invaders like bacteria, viruses and parasites. If you find that you’re frequently sick, you may not be getting the vitamins and nutrients you need. These quick, easy self-tests that can help you find out what you’re missing.

The Sternum Thumb Test for Vitamin D

Vitamin D helps to keep the "guards" of your immune system alert, and is also important for bone and muscle health.

What to do: Take your thumb and press it against your breastbone, which is your sternum. (You can also press on your shinbone as an alternative.) If it feels tender or if it hurts when you press down, you may have a vitamin D deficiency. Though there are some dietary sources of vitamin D (salmon and other fatty fish, fortified milk and cereals), it has been estimated that 90 percent or more of our required vitamin D comes from exposure to sunlight. Read this daily dose on Vitamin D to learn more about how you can replenish your stores.

The Balance Test for Vitamin B12

Low levels of vitamin B12 can not only compromise your immunity but also cause your energy levels to dip. A B12 deficiency can also alter your ability to think clearly.

What to do: Stand up. Put your feet together with your hands on your sides. Then, close your eyes and stick out one of your legs in front of you, and try to hold it for three seconds. (You may want to do this near a wall or a loved one for support.) If you start to lose your balance, it could mean you're low on vitamin B12 (although it could also mean that you just have bad balance). You can find ample sources of vitamin B12 in clams, liver, fish, yogurt and cheese. Vegetarians may want to consider taking a daily vitamin B supplement or multivitamin.

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