On Guard

On Guard

If you’ve had your first colonoscopy and your doctor found no polyps – good news – your chances of ever developing colorectal cancer would appear to be pretty slim. That’s the conclusion of a Sloan-Kettering study I told you about in the e-Alert “Super Bug” (10/31/07).

But what if polyps ARE found?

No need to panic. Polyps are routinely removed during colonoscopy. But now the patient is on notice: Regular follow-up screening to monitor development of polyps is a must, making sure none turn into tumors.

In addition, a new study provides some very encouraging news about colorectal cancer prevention for patients who have already developed polyps.

Polyp control

In previous e-Alerts about colorectal cancer, we’ve seen how folate intake has been frequently linked to prevention of this very common cancer.

Now a UK team, led by researchers at the University of Sheffield, shows that folate’s protection may be significantly increased with supplements of another vitamin in the B complex: riboflavin – also known as vitamin B-2.

STUDY PROFILE

• Researchers recruited 106 subjects with colorectal polyps and nearly 100 healthy subjects
• Subjects were randomly sorted into four intervention groups
• Two groups received either 400 or 1,200 micrograms of folic acid daily
• One group received 400 micrograms of folic acid and 5 milligrams of riboflavin daily
• One group received a placebo
• The intervention period lasted from six to eight weeks
• Analysis of blood samples and biopsy samples showed that folic acid supplementation increased folate levels in the blood and the mucosal layer of the colon (the higher dose created higher folate levels)
• When riboflavin was combined with folic acid, the response was enhanced, but only in subjects with polyps – not in the healthy subjects

Eat up!

In addition to enhancing the cancer preventive effects of folate, riboflavin also helps keep eyes and skin healthy, and has been shown to reduce the frequency of migraine headaches. Riboflavin is water soluble, which means your body needs to be replenished every day. Excessive alcohol consumption and the use of oral contraceptives may prompt riboflavin deficiency.

Foods that contain good amounts of riboflavin include leafy green vegetables, whole grains, meat, eggs, yogurt, cheese, and milk.

And while we’re working on the grocery list, we can add these sources of folate: citrus fruits, tomatoes, leafy green vegetables, avocados, bananas, asparagus, whole grains, and pinto, navy, and kidney beans.

But we’re not done yet, because another member of the B family also helps fight against colorectal cancer.

This past summer I told you about a study that followed dietary and medical records for more than 81,000 subjects over 14 years. Subjects with the highest B-6 intake reduced colorectal cancer risk by more than 30 percent compared to subjects with the lowest intake of the vitamin.

Dietary sources of B-6 include meat, poultry, fish, beans, fruits, and vegetables. Bananas and chicken breast contain particularly high amounts of B-6.

Sources:
“Responses of Biomarkers of Folate and Riboflavin Status to Folate and Riboflavin Supplementation in Healthy and Colorectal Polyp Patients (The FAB2 Study)” Cancer Epidemiology, Biomarkers & Prevention, Vol. 16, No. 10, October 2007, cebp.aacrjournals.org