Many people know that calcium is important in maintaining healthy bones as you age. But did you know that your body also needs vitamin D to help it absorb that calcium?
People who don’t get enough vitamin D are at greater risk for bone loss as they age, and children who don’t get enough D may develop soft, brittle bones — a condition known as rickets. In fact, vitamin D does lots of good things for your body, including helping your muscles move, allowing your nerves to carry messages to the brain and your immune system to battle bacteria and viruses.
But getting enough can be a problem, because vitamin D is not naturally present in many foods. That’s why it’s added to foods such as milk, breakfast cereals and some orange juices — and it can also be taken as a supplement. Another way to increase your vitamin D level is through exposure to the sun’s ultraviolet rays.
Getting Vitamin D in Your Diet
The best sources of vitamin D are fatty fish, such as salmon, tuna, sardines and mackerel, or fish liver oils. You can also add small amounts of vitamin D to your diet through beef liver, cheese, egg yolks and mushrooms.
In the United States, most milk is fortified with vitamin D, but foods made from milk, such as cheese and ice cream, are not fortified. Vitamin D is sometimes added to yogurt, margarine and soy beverages. Read the labels when you’re food shopping to be sure.
Vitamin D Supplements
Vitamin D can also be found over-the-counter in a variety of strengths and combinations — including with calcium, and/or magnesium. It also comes in a variety of forms: tablets/capsules, liquid and chewable “candies.” Make sure you discuss with your pharmacist the strength needed for your age and activity level, as well as which form of the vitamin your body would be best absorb.
The Role of the Sun
When the sun hits your skin, it triggers the production of vitamin D. But this only occurs through direct exposure to the sun’s ultraviolet rays (not through a window when you’re indoors, or when it’s cloudy). Sunscreen — which is needed to protect the body from skin cancer — reduces the amount of vitamin D your body will produce due to sun exposure, as does dark-colored skin. Because of this, sun exposure is not an ideal way to increase vitamin D levels. You may need to take supplements to be sure you’re getting enough.
Recommendations & Requirements
The National Institutes of Health (NIH) provides recommendations for how much vitamin D you need each day, based upon your age. Most people (those ages 1 to 70) need 600 International Units (IU), as do pregnant and breastfeeding women and teens. Children under the age of one need 400 IU, and adults 71 years and older need the most: 800 IU.
To find out if you are getting enough vitamin D, your healthcare provider will take a blood test. Levels are measured in nanomoles per liter (nmol/L) or nanograms per milliliter (ng/mL). Levels below 30 nmol/L (12 ng/mL) are considered too low for good bone health and those above 125 mol/L (50 ng/mL) are considered too high.
If you aren’t getting enough vitamin D, you may experience bone pain or muscle weakness. Getting too much, however, can be toxic and you may experience nausea, vomiting, poor appetite, constipation, weakness or weight loss. Along with too much calcium, it can cause confusion, disorientation, problems with heart rhythm and kidney damage. Be sure to talk to your provider about your levels and how to maintain the proper balance for your health.