Professors tracked the colon health of 2,058 adults for between three to five years. These patients were split into four groups: a group that took 1,200mg calcium capsules, another that took 1,000mg of vitamin D, a third took a calcium-Vitamin D supplement, and a fourth took a placebo every day. All of the study participants were between 45 and 75 years old and had colon polyps in the past.
Doctors performed colonoscopies on all of the patients throughout the study period. During this time, investigators found no correlations between these vitamins and colon polyps.
When doctors followed up with 1,000 study participants a few years later, however, they discovered a higher rate of colon polyps in the two groups that had taken calcium supplements. The patients who only calcium during the study period had a 2.6 times greater risk and the calcium-vitamin D group had a 3.8 times greater chance of developing colon polyps than the other two groups.
Unsurprisingly, study participants who were smokers were at a greater risk of developing colon polyps. Researchers also found that more women than men were susceptible to polyps over the course of this study.
Scientists involved in this research admit they were surprised by the study results. If anything, they were expecting calcium supplements to have a positive effect on colon health.
While the results from this study are concerning, doctors urge caution when interpreting this data. For a start, everyone involved in this study already had a history of colon polyps. Also, although colon polyps could develop into colon cancer, many remain benign throughout a person’s life.
Before taking calcium supplements, or any supplements for that matter, patients should talk with their doctor about potential risk factors. It’s important to consider the potential interactions calcium could have with other drugs.
Scientists now want to understand why calcium tends to trigger colon polyps. They also would like to test how calcium supplements affect the gastrointestinal health of people without a history of colon polyps.
Colorectal cancers are currently one of the most commonly diagnosed cancers in the world. Thankfully, there are many changes everyone could put in place to dramatically reduce their risk of developing colorectal cancers.
This study was published in the journal Gut under the title, “Calcium and vitamin D supplementation and increased risk of serrated polyps: results from a randomised clinical trial.”