Calcium is the most abundant mineral in the body. It’s found naturally in some foods, added to others, available as a supplement and found in some medications. Only 1 percent of the body’s calcium is used for metabolic functions, such as vascular contraction and vasodilation, muscle function, nerve transmission, intracellular signaling and hormone secretion. The remaining 99 percent is found as structural support in your bones and teeth.
So how much calcium do you need? The National Institutes of Health (NIH) provides the following guidance for daily intake:
- Younger than six months: 200 mg
- Six to 12 months: 260 mg
- One to three years: 700 mg
- Nine to 18 years: 1,300 mg
- 19 to 50 years: 1,000 mg
- 51 to 70 years: 1,000 mg for men, 1,200 mg for women
- 71 years and older: 1,200 mg
Many children, teens and adults don’t get enough calcium. Inadequate calcium consumption causes osteopenia (bone loss), which may result in osteoporosis. In addition, you’re more susceptible to bone fractures with poor calcium intake.
In 1984, President Reagan designated July as National Ice Cream month, while noting ice cream is a fun and nutritious food enjoyed by 90 percent of the nation’s population. But how much calcium is in ice cream? NIH says 4 oz. of ice cream has 85 mg. Some other calcium-rich foods:
- Plain low-fat yogurt: 415 mg per 8 oz.
- Cheddar cheese: 307 mg per 1.5 oz.
- Nonfat milk: 299 mg per 8 oz.
- Fortified orange juice: 300 mg per 8 oz.
- Salmon: 181 mg per 3 oz.
- Kale: 100 mg per 1 cup
- Raw broccoli: 21 mg per ½ cup
Calcium content varies slightly by fat content — the more fat, the less calcium. Calcium absorption depends on the total amount of calcium consumed at one time — the higher the amount, the less absorption. However, the presence of vitamin D increases calcium absorption. Recommended intake of calcium at one time is 500 mg or less.
So, the next time you’re shopping for high-calcium foods, search for low-fat yogurt, low-fat milk, cheddar cheese, fortified orange juice and other calcium-containing foods. And when you find yourself looking for a calcium supplement, remember the importance of 500 mg or less per serving for best absorption.
Anne Harguth is a registered dietitian at Mayo Clinic Health System in Waseca.