If you're not sure about how much calcium your body needs, The National Institutes of Health has issued the following guidelines for calcium consumption:
- 1,000 mg/day for women between 25 and 50 years of age.
- 1,200 to 1,500 mg/day for pregnant or lactating women.
- 1,000 mg/day for postmenopausal women on estrogen replacement therapy.
- 1,500 mg/day for postmenopausal women not on estrogen therapy.
- 1,000 mg/day for men aged 25 to 65.
- For all women and men over 65, daily intake is recommended to be 1,500 mg/day, although further research is needed in this age group.
- Calcium intake, up to a total intake of 2,000 mg/day, appears to be safe in most individuals.
As a point of reference, antacid tablets can contain anywhere from 200 to 800 milligrams of calcium, depending upon whether they are regular or extra strength. All the manufacturers do list daily limits on the packaging.
The NIH notes that its guidelines are based on calcium from the diet plus any calcium taken in supplemental form, so it's important that the consumer know how much calcium is in each supplement and pay heed to suggested limits.
Of course, there are other considerations, too. Adequate amounts of vitamin D are essential for optimal calcium absorption. Daily food intake, hormones, drugs, age, and genetic factors also influence the amount of calcium required for optimal skeletal health.
The National Academy of Sciences (NAS) and the National Osteoporosis Foundation say that a healthy way to increase the amount of calcium in your diet is to eat calcium-rich foods such as low-fat milk, yogurt, and cheese. Most people who consume four cups of milk a day will receive an adequate amount of calcium, plus the proper amount of vitamin D needed to absorb it. Also, many foods such as orange juice, cereals, and breakfast bars are fortified with calcium.
Other good dietary sources of calcium include fish, primarily those where you can eat the bones, too, such as sardines, salmon, and smelt. Also on the high-calcium list: collard greens, spinach, broccoli, tahini, tofu (if calcium is added to the liquid), oats and oatmeal, seaweed, and dandelion leaves.