Dear Reader,
Calcium is essential for strong bones, but to enhance the amount of calcium that reaches your bones, you also need vitamin D.
Your body makes vitamin D from two sources — sunlight and food. Most of the vitamin D in your body results from sun exposure. When you’re exposed to ultraviolet light rays, a chemical in your skin is converted into a form of vitamin D. Your liver and kidneys then change it into an active form that your body can use.
Egg yolks and fatty fish, such as herring, mackerel and salmon, naturally contain vitamin D. Several food products also are fortified with vitamin D, such as milk and some breakfast cereals.
Some people don’t get enough vitamin D, either due to lack of exposure to sunlight or not eating foods that contain the vitamin. In addition, with age, the skin becomes less efficient at synthesizing vitamin D, and the body is less able to absorb it from food.
If you don’t eat foods containing vitamin D or you rarely spend time outdoors, you might want to take a vitamin D supplement to meet your daily requirement. The recommended amount is 600 international units (IUs) daily through age 70 and 800 IUs for adults older than age 70. Some researchers and organizations suggest 1,500 to 2,000 IUs daily for optimal health. Talk to your doctor about the amount that’s best for you.
Excessive sun exposure isn’t healthy for your skin, but a little bit of sun — about 15 minutes a day — can be good for your bones. | 
