Calcium is usually safe for most people as long as it’s taken appropriately in its recommended doses. The Institute of Medicine has set the daily tolerable upper intake level (UL) for calcium based on age as:
- 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
You should avoid taking high calcium doses than this.
Taking higher doses than the daily tolerable upper intake level (UL) might also increase the risk of heart attack. Be sure to consider your total calcium intake from both dietary and supplemental sources and avoid exceeding 1000-1300 mg per day.
- Pregnancy and breast-feeding: Calcium is generally safe when it’s used in recommended amounts during pregnancy and breast-feeding.
- High levels of phosphate in the blood (hypophosphatemia) or low levels of phosphate in the blood (hypophosphatemia): calcium and phosphate should be in a proper balance in order for the body to stay healthy. Taking too much calcium may cause an imbalance and cause harm. Consult your health provider before taking excess calcium.
- Underactive thyroid (hypothyroidism): Calcium may interfere with thyroid hormone replacement treatment. Calcium and thyroid medications should be taken separately and at least 4 hours apart.
- Extra calcium in the blood (parathyroid gland disorders and sarcoidosis): Calcium should be avoided if you have any of these conditions.