An analysis of the results of a large study shows that taking calcium with or without vitamin D increases the risk of certain polyps - precancerous growths in the large intestine.

For such complications, it seems that 3-5 years of regular calcium intake is sufficient..

Alarming evidence comes from a 10-year randomized clinical trial that tested the safety of calcium and vitamin D. Details are published by Gut magazine.

If confirmed, this could have serious implications for the screening and prevention of bowel cancer.. And fans of dietary supplements will have a sad reason for reflection..

Does Calcium Prevent Bowel Cancer

This question has worried Western doctors for several years, but similar studies conducted in 2016-2017 could not give an unambiguous answer..

Meanwhile, colorectal cancer is one of the most common cancers.. Every year 50 thousand new cases of intestinal cancer are diagnosed in Russia, and mortality from it is one of the highest.

Cancer starts with harmless polyps.

Colorectal cancer usually starts as a polyp, a mass in the lumen of the intestine that is characterized by uneven growth. Polyps grow very slowly, often up to 20 years..

There are different types of polyps that differ in shape, size, and tissue characteristics..

The most common among them is adenomatous intestinal polyp, or adenoma.

A new study by researchers from several research centers in the United States focused on another, less common type of polyps - the so-called serrated polyps (SSL).

“While routine colonoscopic screening to remove suspicious polyps is an ideal way to reduce the incidence of cancer from a clinical perspective, population-wide adoption is limited in practice for a variety of reasons, including affordability and cost,” the authors say..

Therefore, researchers and doctors are interested, in addition to screening, the possibility of cancer chemoprevention with available drugs - folic acid, vitamin D aspirin, non-steroidal anti-inflammatory drugs or the same calcium.

But reality turned out to be not at all what we would like.

Calcium leads to bowel cancer?

New study was to confirm the preventive properties of calcium and vitamin D in 2,259 patients aged 45-75. All participants had at least one adenomatous intestinal polyp removed during screening. The next colonoscopy was planned in 3-5 years.

Subjects with a family history of inflammatory bowel disease were excluded from the study, and the rest were randomly assigned to 4 groups..

The first group received daily supplements with calcium, the second - vitamin D, the third - calcium along with the vitamin, the fourth group did not receive any vitamin and mineral supplements at all.

All groups remained on their chart until the next colonoscopy performed 3-5 years later. This was followed by an observation phase during which the participants took no supplements.. The multistage study ended with the third screening colonoscopy, which was performed 6-10 years after the start of admission.

Results showed that neither calcium nor vitamin D prevented polyp formation.

The third colonoscopy, carried out 6-10 years after the start of the project, presented an unpleasant surprise: serrated polyps were more common in subjects taking calcium alone or with vitamin D!

Vitamin D alone had no effect on the risk of polyps..

Women and smokers who took calcium were at greatest risk.

Despite the shocking findings, the authors advise not to panic and wait for more research..

In the meantime, it is worth recalling that long-term calcium intake must be coordinated with a doctor.!

medbe. ru.