Calcium and Bone Health

Calcium in the Body

Most of the calcium in the body is in the bones. There is a tiny amount in the blood stream which is responsible for important functions such as muscle contraction, maintenance of the heartbeat, and transmission of nerve impulses. We constantly lose calcium from our blood through urine, sweat, and feces. It is restored with calcium from the bones. To maintain bone calcium, we must get enough calcium from our diet.

Although specific dietary needs may differ for certain age groups, getting enough calcium is always important. Calcium needs are the greatest during adolescence and young adulthood. For that reason, it is recommended that individuals in those age groups eat between 1,000-1,300 mg calcium per day to maximize bone health.

A number of factors may affect how well calcium is used for building bones:

Exercise slows bone loss and is one of the most important factors in maintaining bone health.
Diets that are high in protein, caffeine, and salt cause more calcium to be lost through the urine.
Alcohol and smoking inhibit calcium absorption.

Where Can I Find Calcium?

Dairy products such as milk, yogurt, and cheese are excellent sources of calcium. There are non-dairy food sources of calcium as well including dark green leafy vegetables, such as bok choy and broccoli, almonds, and some grains. Some foods are fortified with calcium including calcium set tofu, and fortified orange juice, cereals, and soy or nut milks.

Yogurt1 cup415
Cheddar Cheese1.5 oz307
Milk1 cup293
Soymilk1 cup299
Orange Juice (fortified)6 oz261
Tofu, firm1/2 cup253
Salmon, canned3 oz181
Turnip Greens, cooked1/2 cup103
Kale, raw1 cup100
Broccoli, raw1/2 cup21

For more information visit:
NIH: Calcium Fact Sheet Dairy – What is Calcium?

Information adapted from the Center for Disease Control and Prevention