Calcium

This fact sheet is one in a series containing information to help you select foods that provide adequate daily amounts of vitamins, minerals, and dietary fiber. Following these guidelines will help align your diet with the Dietary Guidelines for Americans.

What is Calcium?

Calcium is the most abundant mineral in the body, making up 1 to 2 percent of your body weight. Ninety-nine percent of calcium is in teeth and bones. The other 1 percent is found in blood, extra cellular fluids, and within cells of all tissues where it regulates key metabolic functions.

Why is Calcium Important?

Calcium is needed for achieving optimal bone health. Calcium also keeps the heart pumping, muscles moving, and nerves communicating. Each day, our bodies lose calcium through bodily fluids, skin, and hair. Because our bodies can’t produce more calcium on their own, it must be replaced for good health.

When we don’t consume enough calcium, it is salvaged from bones. Low intake of calcium over a lifetime may lead to less dense bones, increased risk of osteoporosis, and increased risk for bone fractures.

How Much Calcium Should We Consume?

Our bodies’ absorption of calcium from food and drink varies across time and people. Age, metabolism, food intake, and women’s pregnancy status all influence calcium absorption. This means the amount of calcium we should consume varies throughout the life cycle. The recommended amounts of calcium intake throughout the lifecycle are shown in Table 1.

Why is There Concern Over Calcium Intake?

Statistics from the most recent National Health and Nutrition Examination Survey (NHANES) (which tracks Americans’ diets) show that 41% of youth (2-18) and 36% of adults (19+) do not consume the recommended amount of calcium. Due to the large number of people with insufficient calcium, the U.S. Department of Agriculture (USDA) considers dietary calcium a public health concern.

While calcium consumption is a concern across all U.S. populations, there are certain groups at high risk for not obtaining enough calcium in their diets. These groups include those on special meal plans (such as vegan diets and lactose-free diets), women capable of becoming pregnant who exercise heavily and/or eat too little, and postmenopausal women.

Why is Dairy Important to Calcium Intake?

Dairy is the greatest source of calcium in the U.S. food supply, accounting for 50% of Americans’ calcium intake. One cup of dairy contains roughly 300 mg of calcium.

The 2015-2020 Dietary Guidelines recommend individuals following a healthy U.S.-style diet consume the following dairy amounts:

• Children 2-3: 2 cups of dairy per day
• Children 4-8: 2½ cups of dairy per day
• Youth 9-18: 3 cups of dairy per day
• Adults: 3 cups of dairy per day

Unfortunately, the average American consumes only 52% of the daily dairy amounts recommended above (roughly 1½ cups for youth and adults). Research has shown that increasing dairy consumption to recommended levels can eliminate calcium deficiencies in diets.

What are Healthy Dairy Choices?

While dairy products provide calcium, some are also high in saturated fat and calories. To make smart dairy decisions, the 2015-2020 dietary guidelines recommend we consume low-fat or fat-free dairy products.

When shopping at the store, purchase:

• Fat-free/skim or 1% milk
• Cheese made from 1% or 2% milk/ reduced-fat or non-fat cheese
• Non-fat or low-fat yogurt

What are Non-dairy Sources of Calcium?

If you don’t consume dairy for health reasons (e.g., lactose intolerance) or other personal reasons (e.g., dietary restrictions due to religious beliefs), it is still possible to obtain necessary levels of calcium in your diet through non-dairy food sources.

Non-dairy sources of calcium include:

• Juices with added calcium and vitamin D
• Cereals, breads, and other grains fortified with calcium
• Calcium-fortified soy milk, soy-yogurt, and soybeans
• Calcium-fortified rice milk and almond milk
• Canned fish, including mackerel, bone-in salmon, and sardines
• Fortified tofu
• Garbanzo, pinto, and white beans
• Broccoli, spinach, kale and other green vegetables

The amount of calcium absorbed will vary across the types of food.

How Do You Identify Foods Rich in Calcium?

	Figure 1: Example Nutrition Label
	Nutrition label created through onlinelabels.com

The most important step in identifying calcium-rich foods is to read the nutrition label. A calcium rich food will include “calcium” within its list of vitamins and minerals. The label will show the percentage of daily calcium obtained by consuming 1 serving of the food or drink. See figure 1.

Food companies also advertise their products according to regulations set by the Food and Drug Administration (FDA). The FDA requires food companies to use specific language when advertising calcium and other mineral content:

• If a food product advertises “high,” “rich in,” or “excellent source,” it must provide 20% or more of calcium’s daily value (DV) per recommended serving of the product.
• If a food product advertises “good,” “contains,” or “provides,” it must provide 10-19% of calcium’s DV per serving.
• If a product advertises “enriched,” “more,” “fortified,” “added,” “extra,” or “plus,” it must provide at least 10% of calcium’s DV per serving.

Do Dietary Supplements Aid Calcium Intake?

NHANES data show that 43% of the U.S. population report using calcium supplements. Many Americans are able to achieve recommended calcium intakes through calcium-rich diets alone. If you struggle to meet recommended calcium intake levels through food and beverages alone, supplements can serve as important dietary aids.

If you choose to use dietary supplements, make sure to use a calcium supplement that contains vitamin D. Vitamin D plays a key role in your body’s absorption of calcium. For additional information on calcium supplements and their side effects visit: MayoClinic.org

References

MyPlate shows where the Dairy Group belongs within a Healthy Diet: Visit choosemyplate.gov for the latest tips and recommendations on keeping a healthy diet. Image Obtained from United States Department of Agriculture (MyPlate Graphic Resources) [Public domain]

• Bailey, R. L., Dodd, K. W., Goldman, J. A., Gahche, J. J., Dwyer, J. T., Moshfegh, A. J., ... & Picciano, M. F. (2010). Estimation of total usual calcium and vitamin D intakes in the United States. The Journal of Nutrition, 140(4), 817-822.
• Del Valle, H. B., Yaktine, A. L., Taylor, C. L., & Ross, A. C. (Eds.). (2011). Dietary reference intakes for calcium and vitamin D. National Academies Press.
• Ervin, R. B., Wang, C. Y., Wright, J. D., & Kennedy-Stephenson, J. (2004). Dietary intake of selected minerals for the United States population: 1999–2000. Energy, 1(5):6.
• Federal Department of Agriculture (January 2013). Guidance for Industry: A Food Labeling Guide (10. Appendix B: Additional Requirements for Nutrient Content Claims). U.S. Department of Health and Human Services.
• National Institute of Health (March 2013). Calcium. U.S Department of Health and Human Services. Retrieved from:
  ods.od.nih.gov/factsheets/Calcium-Consumer/#h5
• Quann, E. E., Fulgoni III, V. L., & Auestad, N. (2015). Consuming the daily recommended amounts of dairy products would reduce the prevalence of inadequate micronutrient intakes in the United States: diet modeling study based on NHANES 2007-2010. Nutrition Journal, 14(1), 1-11.
  nutritionj.biomedcentral.com/articles/10.1186/s12937-015-0057-5
• U.S. Department of Agriculture (January 2016). Dietary guidelines for Americans 2015-2020, eighth edition. United States Department of Health and Human Services. Retrieved from:
  health.gov/dietaryguidelines/2015/guidelines
• U.S. Department of Agriculture (June 2015). Dairy. Choosemyplate.gov. Retrieved from:
  choosemyplate.gov/dairy