|What Is Calcium?
Calcium is a mineral that your body needs to
build and maintain strong bones. It is not produced within the body so it must come from
outside sources. It is an integral part in the war against Osteoporosis,
along with regular weight-bearing exercise (such as walking) and hormone replacement
Why is it Important?
Everyone can benefit from strong bones. Since
peak bone mass is reached between age 25-35, it is important to start calcium
supplementation as early in life as possible (as in our teenage years). Developing strong
bones early on helps prevent the weakening that naturally occurs later in life. Young
female athletes, dancers, and those with low body weight are at risk for brittle bones.
How much do I need?
A simplified recommended daily allowance (RDA) for calcium is as
Women under age 50 and Men under 65: 1200 mg
of Elemental Calcium daily .
Women over age 50 and Men over 65: 1500 mg of
Elemental Calcium daily.
Younger people: 1000 mg of Elemental Calcium
daily (about three servings of milk, yogurt, or cheese).
Where can I find it?
Calcium may be obtained from two main sources: foods and
Food sources - the best sources of
calcine are from foods, such as dairy products, but they can be high in fat so go for the
low fat versions (like 1 or 2% milk). Other good sources are found in nuts, tofu, smelt,
sardines, salmon & shrimp. Smaller amounts are found in various other vegetables,
fruits, proteins & grains.
Supplements Calcium is available in
different combinations (calcium carbonate, citrate, lactate, gluconate, and phosphate).
Each has a different rate of absorption as well as different effects on the
gastrointestinal tract. You will likely find the widest selection at a health-food store.
Buy a supplement labeled "USP." These letters on a label mean that the product
meets the U.S. Pharmacopoeia's standard for dissolving and for dosage. Chewables are
probably absorbed better since the dissolving process starts in your mouth.
Calcium citrate has the advantage of being absorbed when gastric
acid secretion is low (very common after menopause and in those taking acid reducing
medications). In addition, the citrate form is protective against the formation of
calcium-rich kidney stones.
The RDA for calcium intake is based on the amount of
elemental calcium in the supplement you take. You will need to look carefully at
the packaging of you supplement to find out just how much elemental calcium you are
getting. For example, TumsŪ contains "500mg" of calcium carbonate, but only
200mg of its calcium carbonate is in the elemental form. In order to get 1000 mg. of
elemental calcium, you would need to take five TumsŪ per day, not just two.
These minerals help to strength our bones and have
other benefits as well. If you are at an increased risk for Osteoporosis,
we recommend shopping for a calcium supplement that already contains these ingredients, or
take them as an additional supplement.
You may also consider increasing your intake of the
Zinc: About half of all women
consume less than the recommended dietary allowance (RDA) for zinc, which is 12
milligrams per day.
Fluoride. A fluoride intake of 1.5
to 4 mg. a day is considered safe and may increase calcium retention and reduce
the incidence of dental cavities.
How do I take supplements?
Your calcium is best taken with meals, such as a
calcium rich food (milk or orange juice) and not with a high-fiber food (such as cereal).
This increases the likelihood of absorption. The presence of other nutrients (such as
vitamin D and certain amino acids) also promotes absorption. You should not take more than
500 milligrams at a time. If you're taking 1,000 milligrams a day, divide it into two
doses. Calcium is also more efficiently absorbed at night, so take one of your doses
Blockers of Calcium Absorption
Alcohol, caffeine, smoking, excess phosphorus
(in carbonated beverages) excess protein (ie. high protein diets), and antacids containing
aluminum hydroxide all contribute to either depleting calcium from your bones or
preventing absorption. Remember... everything in moderation!
If you are taking the antibiotic tetracycline,
corticosteroids, or iron pills, talk with your doctor or pharmacist. Calcium can interact
with these and other drugs.
A study published in the June 2000 issue of the
prestigious Journal of the American Medical Society has demonstrated that initiation of
supplementation with calcium carbonate can reduce the absorption of levothyroxine, a
commonly used hormone for the treatment of hypothyroidism ("underactive
thyroid"). You should talk to your doctor about having your thyroid tests repeated
about one month after starting calcium supplementation. It is not known if this effect on
thyroid hormone absorption occurs with use of other supplements besides calcium carbonate.
Quantities of foods containing 500 mg of Elemental
Milk - 14 oz.
Milk - 8 oz.
Vanilla milkshake -
Swiss cheese - 2
Cottage Cheese - 3
Cheddar Cheese - 2
low-fat - 10 oz.
Ice cream - 2 3/4
Custard - 1 2/3
Macaroni and cheese
- 1 1/4 cups
Tofu - 1 3/4 cups
Cheese pizza - 3
Sardines - 11
- Salmon (canned, with bones) - 9 oz.
Strategies to increase your calcium intake
The average calcium intake of menopausal women
in the U.S. is only about 500 mg. a day. It takes a bit of thought to increase your
calcium intake without excessively increasing your calories too. In addition to helping
reduce bone loss, a high calcium intake is thought to be a protective factor against
cancer of the colon, stroke, hypertension, Premenstrual Dysphoric Disorder (formerly
Premenstrual Syndrome or PMS, and periodontal disease.
The best source of calcium is from your diet! A good
strategy is to include 300-500 mg. of calcium containing foods with each meal and as a
bedtime snack. If this is not possible at any meal, a calcium supplement should be used.