Calcium, vitamin D, and your bones
Osteoporosis - calcium; Osteoporosis - low bone density
Bone Strength and Calcium
Your body needs calcium to keep your bones dense and strong. Low bone density can cause your bones to become brittle and fragile. These weak bones can break easily, even without an obvious injury.
Vitamin D helps your body absorb calcium. Eat foods that provide the right amounts of calcium, vitamin D, and protein. This kind of diet will give your body the building blocks it needs to make and maintain strong bones.
How Much Calcium and Vitamin D Do I Need?
Amounts of calcium are given in milligrams (mg), and vitamin D is given in international units (IU).
All adults under age 50 should have:
- 1,000 mg of calcium daily
- 400 to 800 IU of vitamin D daily
Adults age 51 and older should have:
- Women: 1,200 mg of calcium daily
- Men: 1,000 mg of calcium daily
- Men and women: 800 to 1,000 IU of vitamin D daily
Calcium and Dairy Products
Milk and dairy products are the best sources of calcium. They contain a form of calcium that your body can absorb easily. Choose yogurts, cheeses, and buttermilk.
Adults should choose fat-free (skim) milk or low-fat (2% or 1%) milk, and other lower fat dairy products. Removing some of the fat does not lower the amount of calcium in a dairy product.
- Yogurt, most cheeses, and buttermilk come in fat-free or low-fat versions.
- Vitamin D helps your body use calcium, which is why vitamin D is often added to milk.
If you eat very few or no dairy products, you can find calcium in other foods. It is often added to orange juice, soy milk, tofu, ready-to-eat cereals, and breads. Check the labels on these foods for added calcium.
Other Sources of Calcium
Green leafy vegetables, such as broccoli, collards, kale, mustard greens, turnip greens, and bak choy (Chinese cabbage), also spelled "bok" choy, are good sources of calcium.
Other good food sources of calcium are:
- Salmon and sardines that are canned with their bones (you can eat these soft bones)
- Almonds, Brazil nuts, sunflower seeds, tahini (sesame paste), and dried beans
- Blackstrap molasses
Other tips to make sure your body can use the calcium in your diet:
- Cook high-calcium vegetables in a small amount of water for the shortest possible time. They will retain more calcium this way.
- Be careful about what you eat with calcium-rich foods. Certain fibers, such as wheat brain and foods with oxalic acid (spinach and rhubarb), can prevent your body from absorbing calcium.
Your doctor may recommend a calcium or vitamin D supplement for the calcium and vitamin D you need.
Lewiecki EM. In the clinic. Osteoporosis. Ann Intern Med. 2011 Jul 5;155(1):ITC1-1-15;quiz ITC1-16.
National Osteoporosis Foundation. Clinician's Guide to Prevention and Treatment of Osteoporosis. Washington, DC: National Osteoporosis Foundation; 2010. Available at: my.nof.org/bone-soruce/education/clinicians-guide-to-the-prevention-and-treatment-of-osteoporosis. Accessed 5/17/2014
National Osteoporosis Foundation. Vitamin D and bone health. Osteoporosis Clinical Updates 2012. Available at: my.nof.org/bone-source/eduction/clinical-updates/clinical-updates-vitamin-d-and-bone-health. Accessed 5/17/2014.
Reviewed By: C. Benjamin Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.