Does calcium supplements cause constipation
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The Impact of Calcium Supplements on 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 constipation. This article synthesizes findings from multiple research studies to determine whether calcium supplements indeed cause constipation.
Research Findings on Calcium Supplementation and Constipation
No Significant Impact on Stool Frequency or Form
A study conducted on healthy women explored the effects of calcium supplementation on gut motility. In this 8-week randomized, double-blind, crossover pilot study, participants received 500 mg/day of elemental calcium from either calcium carbonate or calcium phosphate. The results indicated no significant differences in stool frequency or form across the different periods of the study. Stool frequency averaged 1.3 stools per day, and the percentage of stools indicative of slow transit or constipation remained consistent across all periods, including the baseline and washout periods. This suggests that calcium supplementation at the given dosage does not significantly affect bowel movements in healthy women.
Occasional Gastrointestinal Side Effects
While the aforementioned study found no significant impact on constipation, another review of randomized controlled trials (RCTs) reported a higher incidence of gastrointestinal (GI) adverse events in participants receiving calcium supplements. These adverse events included constipation, abdominal cramping, bloating, and other GI symptoms. The relative risk of experiencing GI adverse events was higher in the calcium group compared to the placebo group (14.1% vs. 10.0%). This indicates that while calcium supplements may not universally cause constipation, they can lead to GI discomfort in some individuals.
Comparison of Calcium Carbonate and Calcium Citrate
Different forms of calcium supplements may have varying effects on the digestive system. Calcium carbonate, a common form of calcium supplement, has been noted to occasionally cause constipation, intestinal bloating, or excess gas. On the other hand, calcium citrate is generally better absorbed and causes fewer of these side effects. This suggests that individuals who experience GI discomfort with calcium carbonate might benefit from switching to calcium citrate.
Conclusion
The relationship between calcium supplements and constipation is not straightforward. While some studies indicate no significant impact on stool frequency or form, others report a higher incidence of GI adverse events, including constipation, in individuals taking calcium supplements. The form of calcium supplement also plays a role, with calcium citrate being less likely to cause GI discomfort compared to calcium carbonate. Therefore, individuals concerned about constipation or other GI side effects may consider trying different forms of calcium supplements and monitoring their body's response.
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