Is excess calcium harmful to health?
Study Goal
The researchers aimed to evaluate the safety and efficacy of calcium supplementation in preventing osteoporosis and fractures, while also assessing potential adverse effects on vascular health.
Results Summary
The study found that calcium supplementation may increase the risk of myocardial infarction by ~30%, raising concerns about its safety, but it remains recommended for osteoporosis prevention at 1,000–1,300 mg/day. Mixed evidence exists regarding its effects on vascular disease, blood pressure, lipid levels, and vascular calcification.
Population
Older adults and the elderly.
Effective Dosage
1,000–1,300 mg/day (total intake from diet and supplements).
Duration
Not specified.
Interactions
None mentioned.
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
total calcium intake (diet and supplements) of 1,000 to 1,300 mg/day | decrease | osteoporosis and fractures | older adults and the elderly | - | prevent | #1 |
calcium supplements | increase | myocardial infarction | - | ~30% | associated with an increased risk | #2 |
calcium supplements | increase | vascular disease | - | - | associated with potential adverse effects | #3 |
calcium supplements | increase | mortality | - | - | associated with potential adverse effects | #4 |
high levels of calcium | decrease | health | - | - | harmful to health | #5 |
calcium supplementation | neutral | vascular disease | - | - | effects | #6 |
calcium supplementation | neutral | blood pressure | - | - | effects | #7 |
calcium supplementation | neutral | lipid and lipoprotein levels | - | - | effects | #8 |
calcium supplementation | neutral | vascular calcification | - | - | effects | #9 |
Most current guidelines recommend that older adults and the elderly strive for a total calcium intake (diet and supplements) of 1,000 to 1,300 mg/day to prevent osteoporosis and fractures. Traditionally, calcium supplements have been considered safe, effective and well tolerated, but their safety has recently been questioned due to potential adverse effects on vascular disease which may increase mortality. For example, the findings from a meta-analysis of randomized controlled trials (currently published in abstract form only) revealed that the use of calcium supplements was associated with an ~30% increased risk of myocardial infarction. If high levels of calcium are harmful to health, this may alter current public health recommendations with regard to the use of calcium supplements for preventing osteoporosis. In this review, we provide an overview of the latest information from human observational and prospective studies, randomized controlled trials and meta-analyses related to the effects of calcium supplementation on vascular disease and related risk factors, including blood pressure, lipid and lipoprotein levels and vascular calcification.