Folic Acid May Fight Throat Cancer
Early Tests Show Promise Against Laryngeal Cancer, Researchers Report
June 12, 2006 -- The B vitamin folic acid, also called folate, is being studied as an anticancer agent to help prevent cancerof the larynx.
Folic acid is found in dark green, leafy vegetables (such as spinach and turnip greens), dried beans and peas (including black-eyed peas and lentils), and foods fortified with folic acid (including enriched grain products). Folic acid is also available from supplements.
Doctors in Italy recently studied folic acid's effects on laryngeal leukoplakia, which are precancerous lesions in the larynx. While more tests are needed, early results showed laryngeal leukoplakia didn't turn into cancer while patients were taking folic acid supplements, and – in some patients – the precancerous lesions disappeared.
The researchers included Giovanni Almadori, MD, who works at the Universita Cattolica del Sacro Cuore's Institute of Otolaryngology in Rome. Results appear in the early online edition of the journal Cancer.
Almadori's team had previously reported that people with laryngeal leukoplakia tend to have lower blood levels of folic acid than people without laryngeal leukoplakia.
Folic Acid Supplements
So the researchers gave folic acid supplements to 43 adults with laryngeal leukoplakia for six months.
The patients had lower blood levels of folic acid than people without laryngeal leukoplakia when the study started.
European countries don't fortify grain products with folate, according to the nonprofit European Food Information Council's web site. And the patients hadn't taken supplements of folic acid, or the closely-related vitamin B 12, in the previous six months.
The patients weren't heavy drinkers, but more than 80% were smokers. Smoking and heavy alcohol use can boost the risk of laryngeal leukoplakia, the researchers note.
Checking for Cancer
Every eight hours, participants took oral supplements containing five milligrams (mg) of folic acid.
Blood levels of folic acid rose in the patients during the study. Meanwhile, blood levels of homocysteine – an amino acid that at elevated levels has been associated with increased risk of cancer and heart disease-- fell, the researchers report.
Doctors checked the participants' laryngeal leukoplakia every 30 days.
The participants' laryngeal leukoplakia didn't progress to cancer during the study. In addition, 12 patients (28%) had a "complete response," meaning the laryngeal leukoplakia faded away, the researchers write.