• The Who, What, Where, When and Sometimes, Why.
  • Calcium

  • For preventing low calcium levels: 1 gram elemental calcium daily is typically used.
  • For heartburn: Calcium carbonate as an antacid is usually 0.5-1.5 grams as needed.
  • For prevention of weak bones (osteoporosis): Doses of 1-1.6 grams elemental calcium daily from foods and supplements. Osteoporosis treatment guidelines in North America currently recommend 1200 mg daily of calcium.
  • For prevention of bone loss in premenopausal women over 40: A dose of 1 gram.
  • For pregnant women with low dietary calcium intake: The dose for increasing fetal bone density ranges from 300-1300 mg/day beginning at gestation week 20-22.
  • For premenstrual syndrome (PMS): 1-1.2 grams calcium per day as calcium carbonate.
  • For reducing thyroid hormone levels in people with chronic renal failure: 2-21 grams calcium carbonate.
  • To prevent bone loss in people taking corticosteroid drugs: Divided daily doses of 1 gram of elemental calcium daily.
  • For high blood pressure: 1-1.5 grams calcium daily.
  • For preventing high blood pressure during pregnancy (pre-eclampsia): 1-2 grams elemental calcium daily as calcium carbonate.
  • For preventing colorectal cancer and recurrent colorectal benign tumors (adenomas): Calcium 1200-1600 mg/day.
  • For high cholesterol: 1200 mg daily with or without vitamin D 400 IU daily has been used in conjunction with a low-fat or calorie-restricted diet.
  • For preventing fluoride poisoning in children: Calcium 125 mg twice daily, in combination with ascorbic acid and vitamin D.
  • For weight loss, increasing calcium consumption from dairy products to total intake of 500-2400 mg/day in combination with a calorie-restricted diet has been used.
  • Calcium carbonate and calcium citrate are the two most commonly used forms of calcium.

    Calcium supplements are usually divided into two doses daily in order to increase absorption. It’s best to take calcium with food in doses of 500 mg or less.

    The Institute of Medicine publishes a recommended daily allowance (RDA) for calcium which is an estimate of the intake level necessary to meet the requirements of nearly all healthy individuals in the population. The current RDA was set in 2010. The RDA varies based on age as follows: Age 1-3 years, 700 mg; 4-8 years, 1000 mg; 9-18 years, 1300 mg; 19-50 years, 1000 mg; Men 51-70 years, 1000 mg; Women 51-70 years, 1200 mg; 70+ years, 1200 mg; Pregnant or Lactating (under 19 years), 1300 mg; Pregnant or Lactating (19-50 years), 1000 mg.

    The Institute of Medicine also sets the daily tolerable upper intake level (UL) for calcium based on age as follows: Age 0-6 months, 1000 mg; 6-12 months, 1500 mg; 1-3 years, 2500 mg; 9-18 years, 3000 mg; 19-50 years, 2500 mg; 51+ years, 2000 mg. Doses above these levels should be avoided.

    Doses over the recommended daily intake level of 1000-1300 mg/day for most adults have been associated with an increased risk of heart attack. Until more is known, continue consuming adequate amounts of calcium to meet daily requirements, but not excessive amounts of calcium. Be sure to consider total calcium intake from both dietary and supplemental sources and try not to exceed 1000-1300 mg of calcium per day. To figure out dietary calcium, count 300 mg/day from non-dairy foods plus 300 mg/cup of milk or fortified orange juice.


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