Do calcium supplements cause constipation
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Do 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 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 calcium supplementation and washout. The mean stool frequency remained consistent at 1.3 stools per day, and the percentage of stools indicative of slow transit or constipation did not significantly change during the supplementation periods .
Occasional Gastrointestinal Side Effects
While the aforementioned study found no significant impact on stool frequency, another source notes that calcium carbonate supplements can occasionally cause gastrointestinal side effects such as constipation, intestinal bloating, or excess gas. Calcium citrate, on the other hand, is reported to cause fewer of these side effects and is generally better absorbed by the body . This suggests that the type of calcium supplement may influence the likelihood of experiencing constipation.
Increased Incidence of Gastrointestinal Adverse Events
A review of randomized controlled trials (RCTs) found that gastrointestinal adverse events were more common in participants receiving calcium supplements compared to those receiving a placebo. These adverse events included constipation, excessive abdominal cramping, bloating, and other gastrointestinal symptoms. The relative risk of experiencing these events was significantly higher in the calcium group (14.1%) compared to the placebo group (10.0%) . This indicates that while not all individuals may experience constipation, there is a notable increase in gastrointestinal issues among those taking calcium supplements.
Conclusion
The relationship between calcium supplements and constipation is complex. While some studies suggest no significant impact on stool frequency or form, others report occasional gastrointestinal side effects, including constipation, particularly with calcium carbonate. Additionally, a review of multiple RCTs indicates a higher incidence of gastrointestinal adverse events in those taking calcium supplements. Therefore, individuals considering calcium supplementation should be aware of these potential side effects and may want to choose calcium citrate over calcium carbonate to minimize the risk of constipation.
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