Research paper
A Trial of Calcium and Vitamin D for the Prevention of Colorectal Adenomas.
Study answer
What this study found
Daily vitamin D3, calcium, or their combination did not significantly reduce recurrent colorectal adenomas over 3 to 5 years. For one or more adenomas, the risk ratio was 0.99 (95% CI 0.89 to 1.09) for vitamin D vs no vitamin D, 0.95 (95% CI 0.85 to 1.06) for calcium vs no calcium, 1.01 (95% CI 0.88 to 1.15) for calcium plus vitamin D vs calcium alone, and 0.93 (95% CI 0.80 to 1.08) for calcium plus vitamin D vs neither agent. Advanced adenomas were also unchanged, with risk ratios of 0.99 (95% CI 0.75 to 1.29), 1.02 (95% CI 0.76 to 1.38), 0.89 (95% CI 0.63 to 1.26), and 0.99 (95% CI 0.63 to…
- Study & population
- This was a multicenter randomized trial conducted at 11 academic medical centers and associated practices in the United States.
- Intervention
- Participants received oral vitamin D3 1000 IU daily, calcium carbonate 1200 mg daily, or both together as two identical tablets daily.
- Key limitation
- The trial found null effects despite a relatively large sample, and subgroup signals were described as not robust and possibly due to chance.
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Open PDFOriginal abstract
BACKGROUND Epidemiologic and preclinical data suggest that higher intake and serum levels of vitamin D and higher intake of calcium reduce the risk of colorectal neoplasia. To further study the chemopreventive potential of these nutrients, we conduct…