Side effects of too much calcium tablets
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Side Effects of Excessive Calcium Tablets
Calcium supplements are commonly used to support bone health, particularly in populations at risk of osteoporosis. However, excessive intake of calcium tablets can lead to several adverse effects. This article synthesizes findings from multiple studies to highlight the potential side effects of too much calcium supplementation.
Gastrointestinal Issues from Calcium Supplements
Constipation and Abdominal Discomfort
One of the most frequently reported side effects of excessive calcium intake is gastrointestinal (GI) discomfort. Studies have shown that individuals taking calcium supplements experience higher rates of GI issues compared to those taking a placebo. These issues include constipation, excessive abdominal cramping, bloating, and severe diarrhea or abdominal pain. In a review of seven randomized controlled trials (RCTs), the incidence of self-reported GI adverse events was significantly higher in participants receiving calcium supplements (14.1%) compared to those receiving a placebo (10.0%).
Increased Hospitalizations for GI Problems
Further evidence from one study indicated that hospitalizations due to functional GI problems were more common in the calcium group (6.8%) compared to the placebo group (3.6%). This suggests that the severity of GI issues can sometimes necessitate medical intervention.
Cardiovascular Concerns
Misreported Myocardial Infarction (MI)
There is also evidence suggesting that calcium supplementation may be linked to an increased self-reporting of myocardial infarction (MI). However, this increase may be due to non-MI events being incorrectly perceived as MI by patients. In two trials, self-reported MI rates were higher in the calcium group (3.6%) compared to the placebo group (2.1%). After adjudication, the actual MI rates were 2.4% in the calcium group and 1.6% in the placebo group, indicating a potential over-reporting of MI symptoms by those taking calcium supplements.
Metabolic Disorders
Hypercalcemia
Another significant side effect of excessive calcium intake is hypercalcemia, a condition characterized by elevated levels of calcium in the blood. In a study involving elderly women with vitamin D insufficiency, hypercalcemia was reported in 6.3% of the participants taking calcium and vitamin D supplements, compared to 8.3% in the placebo group. Although the difference was not statistically significant, it highlights the potential risk of hypercalcemia with calcium supplementation.
Elevated Serum Uric Acid
The same study also found that the group receiving calcium and vitamin D had significantly higher concentrations of serum uric acid compared to the placebo group (52.3% vs. 37.2%). Elevated serum uric acid can lead to gout and other metabolic complications, indicating another potential risk of excessive calcium intake.
Conclusion
While calcium supplements are beneficial for bone health, excessive intake can lead to several adverse effects, including gastrointestinal discomfort, potential misreporting of cardiovascular events, hypercalcemia, and elevated serum uric acid levels. It is crucial for individuals to consult healthcare providers to determine the appropriate dosage and monitor for any adverse effects during supplementation.
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