Side effects of calcium supplements with vitamin d
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Side Effects of Calcium Supplements with Vitamin D
Introduction to Calcium and Vitamin D Supplementation
Calcium and vitamin D are commonly recommended supplements, especially for bone health. However, their combined use has been associated with various side effects. This article synthesizes research findings on the adverse effects of calcium supplements with vitamin D.
Hypercalcemia and Hypercalciuria
Increased Risk of Hypercalcemia
Long-term supplementation with vitamin D, especially when combined with calcium, has been shown to increase the risk of hypercalcemia. A meta-analysis of 48 studies involving 19,833 participants found that those in the vitamin D group had a significantly higher risk of developing hypercalcemia compared to the placebo group (Relative Risk [RR]: 1.54) .
Elevated Hypercalciuria
Similarly, the risk of hypercalciuria, which is an elevated level of calcium in the urine, was also higher in the vitamin D group (RR: 1.64) . These findings suggest that long-term use of vitamin D and calcium supplements can disrupt calcium metabolism, leading to these conditions.
Kidney Stones
Mixed Evidence on Kidney Stone Formation
The relationship between calcium and vitamin D supplementation and kidney stones is complex. While some studies suggest an increased risk, others do not find a significant association. For instance, one meta-analysis indicated a tendency for fewer kidney stones in the vitamin D group compared to the placebo group, although this was not statistically significant (RR: 0.66) . However, another study reported an increased risk of renal calculi (kidney stones) with calcium and vitamin D supplementation (hazard ratio [HR]: 1.17) .
Cardiovascular Concerns
Potential Cardiovascular Risks
The cardiovascular effects of combined calcium and vitamin D supplementation are still debated. Some studies have reported an increased risk of cardiovascular events, while others have found no significant impact. A review of 14 randomized controlled trials and two meta-analyses concluded that there is no strong evidence to support either beneficial or harmful cardiovascular effects from these supplements . However, the possibility of adverse cardiovascular outcomes cannot be entirely ruled out and warrants further investigation.
Other Health Impacts
Effects on Glucose Metabolism and Lipid Profiles
In a study involving overweight and obese women with polycystic ovary syndrome (PCOS), calcium and vitamin D co-supplementation showed beneficial effects on glucose metabolism and lipid profiles. The study reported decreased serum insulin levels and improved insulin sensitivity, along with reduced serum triglycerides and VLDL-cholesterol levels . These findings suggest that while there are risks, there may also be metabolic benefits in specific populations.
Bone Health and Fracture Risk
Calcium and vitamin D supplementation is often recommended for bone health, particularly in postmenopausal women. Studies have shown that these supplements can increase bone mineral density and reduce the risk of fractures. For example, a systematic review found that combined supplementation significantly increased bone mineral density and reduced the incidence of hip fractures . However, the benefits must be weighed against the potential risks, such as kidney stones and hypercalcemia.
Conclusion
Calcium and vitamin D supplementation can offer benefits, particularly for bone health and metabolic conditions like PCOS. However, they also carry risks, including hypercalcemia, hypercalciuria, kidney stones, and potential cardiovascular issues. Individuals considering these supplements should consult healthcare providers to weigh the benefits and risks based on their specific health needs and conditions. Further research is needed to clarify these risks and optimize supplementation strategies.
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