Research published ahead of print in the journal Gut reports that a purified form of an omega 3 cuts the number and size of precancerous bowel growths (polyps) in people whose genetic make-up predisposes them to bowel cancer.

This particular omega 3 is eicosapentaenoic acid or EPA. It seems to be as effective as the prescription medicine used to treat familial bowel polyps, but without the associated cardiovascular side effects.

The researchers base their findings on 55 patients. All of them had the inherited genetic mutation that prompts the development of precancerous polyps in the bowel. It is known as familial adenomatous polyposis, or FAP.

People with FAP have an increased risk of developing bowel cancer. They require surgery to remove large sections of their bowel. Subsequently, some also need regular monitoring.

Previously, all of the 55 patients had undergone surgery. They were being monitored by endoscopy which is a procedure during which a camera on the end of a flexible tube is passed through the rectum.

Twenty eight of the patients were randomly assigned to six months of treatment. They received 2 g daily of a new highly purified form of the omega 3 polyunsaturated fatty acid (PUFA) EPA. The other 27 were given the same amount of placebo.

To prevent the indigestion that can sometimes be associated with omega 3 supplements, the EPA capsules were enteric coated. Dietary omega 3 PUFA mainly comes from oily fish, such as salmon, mackerel, and herring.

An assessment of the number and size of polyps was carried out at the beginning and end of the six month study period. It revealed significant differences between the two groups of patients.

The number of polyps increased by almost 10 percent among those treated with the placebo. It fell by more than 12 percent among those treated with the EPA capsules. This represents a difference of almost 22.5 percent.

After taking account influential factors, such as age and sex, this was still clinically significant.

In the placebo group, polyp size increased by more than 17 percent. However, it fell by more than 12.5 percent in those taking the EPA capsules, representing a difference of just under 30 percent.

The authors remark that the effects of EPA were similar to those produced by celecoxib. This drug is used to help control the growth of new and existing polyps in patients with FAP.

In older patients, the use of celecoxib has been associated with harmful cardiovascular side effects. In this study, EPA produced few side effects and these were no more common than those produced by the placebo.

The authors suggest that this formulation of omega 3 might also help to prevent bowel cancer in people with the common non-familial form of bowel polyps.

In general, omega 3 PUFAs are safe and even beneficial for cardiovascular health. The authors remark that EPA could be particularly appropriate for older patients at risk of both bowel cancer and heart disease.

“Eicosapentaenoic acid reduces rectal polyp number and size in familial adenomatous polyposis”
Nicholas J West, Susan K Clark, Robin K S Phillips, John M Hutchinson, Roger J Leicester, Andrea Belluzzi, Mark A Hull
Gut Online First
doi 10.1136/gut.2009.200642
Gut

Written by Stephanie Brunner (B.A.)