Calcium Supplementation Guidelines
Recommended Calcium Intake
- The Institute of Medicine recommends daily calcium intake of 1000 mg for women 19-50 years and men 19-70 years, and 1200 mg for women over 50 and men over 70 years 2
- Upper intake levels should not exceed 2500 mg/day for adults under 50 and 2000 mg/day for those over 50 2
- Calcium is a shortfall nutrient in the American diet, making it difficult for many to achieve adequate intake through diet alone 3, 4
Benefits of Adequate Calcium Intake
- Adequate calcium intake is important for skeletal health at all ages 2
- Inadequate calcium intake is associated with increased bone loss and fracture risk, particularly in older adults 2
Sources of Calcium
- Dietary sources are the preferred approach to ensuring adequate calcium intake 2
- When dietary sources are insufficient, supplements may be considered 2
- Common supplement forms include calcium carbonate (40% elemental calcium) and calcium citrate (21% elemental calcium) 2
Supplement Considerations
- For those requiring supplements, divided doses throughout the day improve absorption 5
Vitamin D Considerations
- Vitamin D plays a crucial role in calcium absorption and bone mineralization 5
- The National Osteoporosis Foundation recommends 800-1000 IU of vitamin D daily for adults 50 and older 5
- Serum 25-hydroxyvitamin D levels should ideally be maintained at 30 ng/ml (75 nmol/L) or higher for optimal bone health 5
Safety Considerations
- Calcium supplements may cause gastrointestinal side effects, particularly constipation 2
- There is a modest increased risk of kidney stones with calcium supplementation but not with dietary calcium 2
- The National Osteoporosis Foundation and American Society for Preventive Cardiology state there is moderate-quality evidence that calcium intake from food or supplements has no relationship (beneficial or harmful) to cardiovascular disease risk when kept within recommended limits 3, 4, 6