Calcium, vitamin D, and your bones


Getting enough calcium and vitamin D in your diet can help maintain bone strength and lessen your risk of developing osteoporosis.

Alternative Names

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 more 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.

In addition to getting enough calcium and vitamin D, you can reduce your risk of developing osteoporosis by exercising regularly and avoiding smoking and excessive alcohol use.

Test Your Bone-Health Diet Knowledge

What does your body need to build strong bones?

The correct answer is all of the above. Your body needs calcium to keep bones strong. Too little calcium and bones become brittle and break easily. Vitamin D helps the body take in calcium. Eating foods with the right amounts of calcium, vitamin D, and protein gives your body the building blocks to make and keep strong bones.

How much calcium should adults under age 50 have each day?

The correct answer is 1,000 mg. Women who are 51 or older should have 1,200 mg of calcium daily. To help the body use calcium, adults should also have approximately 800 IU of vitamin D every day.

Dairy products are the best source of calcium.

The correct answer is fact. Milk and dairy products -- such as yogurt, cheeses, and buttermilk -- contain a form of calcium your body can take in easily. Choose low-fat or non-fat dairy products. They have the same amount of calcium with less fat.

If you have lactose intolerance, you can't get enough calcium.

The correct answer is false. People with lactose intolerance have trouble digesting lactose, a type of sugar in milk. There are products you can buy to make it easier to digest lactose. Most grocery stores carry lactose-free milk. If you are lactose intolerant, talk with your doctor about taking a calcium supplement.

Dairy products are the only foods that are rich in calcium.

The correct answer is myth. Calcium is found in many types of vegetables, fish, and nuts. It's also added to some brands of orange juice, soy milk, tofu, cereal, and bread. Read food labels to check for added calcium.

Which vegetable is not a good source of calcium?

The correct answer is spinach. Spinach and rhubarb can prevent the body from absorbing calcium from other foods. Wheat bran can also keep your body from absorbing calcium. Avoid eating these items at the same time as calcium-rich foods.

Which fish is a good source of calcium?

The correct answer is canned salmon or sardines. When these fish are canned with their soft, edible bones, they provide a bounty of calcium. A 2-ounce serving of sardines with bones has 240 mg of calcium. Fish prepared without bones, such as fillets or nuggets, are generally low in calcium.

You should cook vegetables thoroughly to make calcium easy to absorb.

The correct answer is myth. Cook high-calcium vegetables in a small amount of water for the shortest possible time. They will keep more calcium this way.

Which snack is high in calcium?

The correct answer is all of the above. A 3-ounce serving of almonds has 210 mg of calcium, so it's easy to fit in extra calcium at snack time.

It is difficult to get enough vitamin D from food sources alone.

The correct answer is fact. The body makes vitamin D when the skin is exposed directly to the sun. But you may not be able to get enough this way, and few foods contain vitamin D -- mainly dairy products, some cereals, and salt-water fish. If you can't get enough calcium or vitamin D naturally, talk to your doctor about taking extra calcium.

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 children ages 9 to 18 should have:

  • 1300 mg of calcium daily
  • 600 IU of vitamin D daily

All adults under age 50 should have:

  • 1000 mg of calcium daily
  • 400 to 800 IU of vitamin D daily

Adults age 51 and older should have:

  • Women: 1200 mg of calcium daily
  • Men: 1000 mg of calcium daily

Men and women: 800 to 1000 IU of vitamin D daily. People who are vitamin D deficient or have insufficient amounts of vitamin D will need higher amounts of vitamin D supplementation.

Too much calcium or vitamin D can lead to problems such as an increased risk for kidney stones.

  • Total calcium should not exceed 2000 mg per day
  • Total vitamin D should not exceed 4000 IU per day
Calcium source

Calcium source

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 bok choy (Chinese cabbage), 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 bran 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. However, the balance between benefits and harms of these supplements is unclear.


Calcium source
Vitamin D source
Calcium benefit


Brown C. Vitamins, calcium, bone. In: Brown MJ, Sharma P, Mir FA, Bennett PN, eds. Clinical pharmacology. 12th ed. Philadelphia, PA: Elsevier; 2019:chap 39.

Cosman F, de Beur SJ, LeBoff MS, et al. Clinician's guide to prevention and treatment of osteoporosis. Osteoporos Int. 2014;25(10):2359-2381. PMID: 25182228

National Institutes of Health, Office of Dietary Supplements website. Fact sheet for health professionals: Calcium. Updated March 26, 2020. Accessed July 17, 2020.

US Preventive Services Task Force; Grossman DC, Curry SJ, Owens DK, et al. Vitamin D, calcium, or combined supplementation for the primary prevention of fractures in community-dwelling adults: US Preventive Services Task Force recommendation statement. JAMA. 2018;319(15):1592-1599. PMID: 29677309

Review Date: 
Reviewed By: 
Diane M. Horowitz, MD, Rheumatology and Internal Medicine, Northwell Health, Great Neck, NY. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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