Can calcium supplements cause constipation
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Can Calcium Supplements Cause Constipation?
Introduction to Calcium Supplements and Constipation
Calcium supplements are widely used to support bone health, particularly in populations at risk of osteoporosis. However, there is a common belief that calcium supplementation can lead to gastrointestinal issues, including constipation. This article synthesizes research findings to address whether calcium supplements indeed cause constipation.
Research on Calcium Supplementation and Constipation
Study on Healthy Women
A study involving healthy women explored the effects of calcium supplementation on gut motility. Participants received 500 mg/day of elemental calcium from either calcium carbonate or calcium phosphate over an 8-week period. The study found no significant differences in stool frequency or form between the baseline and supplementation periods. Stool frequency averaged 1.3 stools per day across all periods, and the percentage of stools indicative of constipation (Bristol Stool Form Scale of 1 or 2) remained consistent, suggesting that calcium supplementation did not affect bowel habits in these healthy women.
General Side Effects of Calcium Supplements
Another source indicates that while calcium supplements generally cause no side effects, calcium carbonate can occasionally lead to constipation, intestinal bloating, or excess gas. Calcium citrate, on the other hand, is less likely to cause these gastrointestinal issues and is better absorbed by the body. This suggests that the type of calcium supplement may influence the likelihood of experiencing constipation.
Adverse Gastrointestinal Events in Clinical Trials
A review of randomized controlled trials (RCTs) found that gastrointestinal adverse events were more common in participants receiving calcium supplements compared to those on a placebo. These events included constipation, abdominal cramping, bloating, and other gastrointestinal symptoms. The relative risk of experiencing these adverse events was significantly higher in the calcium group (14.1%) compared to the placebo group (10.0%). This evidence supports the notion that calcium supplements can increase the incidence of gastrointestinal issues, including constipation.
Conclusion
The relationship between calcium supplements and constipation is complex and appears to depend on several factors, including the type of calcium supplement and individual differences among users. While some studies suggest that calcium supplements do not significantly affect bowel habits in healthy individuals, others indicate a higher incidence of gastrointestinal adverse events, including constipation, in those taking calcium supplements. Therefore, individuals experiencing constipation with calcium carbonate may consider switching to calcium citrate, which is associated with fewer gastrointestinal side effects.
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