Folic acid’s link to colon cancer lacks hard evidence
Dear Dr. Donohue: I have enclosed an article on why it is dangerous to take more than 400 micrograms of folic acid a day.
I have been on a prescription dose of 1,000 micrograms (1 mg) of folic acid for 10 years. Both my parents died of colon cancer. I am concerned about the level of my dose. I appreciate your opinion.
Dear Dr. Donohue: Recently you
P.T. Folic acid, also called folate, is one of the B vitamins. It has many important functions. It’s essential to the production of red blood cells. It protects body cells’ integrity, aids in the production of both RNA and DNA, and enhances nerve cell performance.
A recently recognized function of folic acid is the prevention of spinalcord malformations in the fetus. Women of childbearing age who intend to become pregnant must pay attention to ingesting 400 micrograms of this vitamin daily. They have to start before they become pregnant and for at least the first 12 weeks of pregnancy. Spina bifida is one of the spinal-cord defects prevented by folic acid. This is the situation where the spinal cord protrudes through a defect in the spinal column (the backbone) and causes severe neurological impairment.
Because it so successfully protects the fetus from spinal-cord deformities, both the Canadian and American governments instituted the fortification of grains and cereals with folic acid in 1998. Since then, there has been a slight upward blip in the number of colon cancer cases, but there has been no definite proof linking food fortification with folic acid to this blip. There has been a downward blip in the number of spina bifida cases.
The safe daily maximum dose of folic acid remains at the dose you're taking. The recommended daily dose is 400 micrograms. had a column on GERD. It is my understanding that GERD can cause esophageal cancer if left uncontrolled. In fact, my 42-year-old neighbour just died from esophageal cancer, and he confided to me that he had GERD for 20-plus years. Am I right?
Dear Dr. Donohue: Please advise what kind of hygiene rules should be used in raising a child. Our son-inlaw’s parents advocate an extreme cleanliness — washing hands many times a day, avoiding sandboxes where other children play and preventing occasional meal sharing. I use common-sense rules like washing hands before meals, letting a child play in groups and avoiding hospitals but not public transportation. Which is preferable?
R.M. You’re on the right track. The fact is that there were 15,560 cases of esophageal cancer in the United States last year. GERD — gastroesophageal reflux disease, or heartburn — is one factor in the genesis of that cancer, but certainly not the only one. The number of people with esophageal cancer is small. The number of people with GERD is large.
Between six per cent and 12 percent of GERD patients will have a change in the kind of cells that line their lower esophagus. When those changes occur, the person is said to have Barrett’s esophagus. Of those with Barrett’s esophagus, a percentage go on to develop esophageal cancer. The danger of cancer is assessed by the kind of cell changes that take place. So-called high-grade dysplasia changes put people at a high risk of cancer, and these people have to be followed frequently with scope exams of their esophagus, or the danger zone has to be removed. People with low-grade dysplasia changes can be followed with less-frequent scope examinations of their esophagus.
Far from everyone with GERD comes down with esophageal cancer. Not everyone with Barrett’s esophagus comes down with esophageal cancer, but these people have to be carefully watched.
V.C. I prefer your approach. You can go overboard on cleanliness. Our bodies are not as delicate as many believe. Furthermore, exposure to germs stimulates the immune system. I believe your son-in-law’s family goes too far.