Men who regularly eat oranges or other foods rich in vitamin C, rather than taking vitamin C supplements, may be reducing their risk for developing oral pre-cancer, according to researchers in Massachusetts.
Researchers evaluated data provided by 42,340 men enrolled in the Health Professionals Follow-up Study, looking at occurrence of oral pre-malignant lesions, dietary supplement use and diet reported in two- to four-year increments between 1986 and 2002.
Participants with the highest dietary vitamin C intake had a 50 percent reduced risk of developing oral pre-cancer as compared to those with the lowest intake. No reduced risks were seen with participants who took vitamin C supplements.
Researchers theorize that some component in vitamin C-rich foods, or an interaction between components, might offer protection from oral pre-cancer and encourage eating a diet that includes vitamin C-rich foods and a variety of nutrients.
Scientists also examined intake of vitamin E, vitamin A and carotenoids and found no clear relationship between oral pre-cancer and beta-carotene, lycopene or lutein/zeaxanthin.
Men who smoked and took vitamin E supplements and/or beta-carotene supplements had an increased risk for oral pre-cancer. Researchers say the increased risk for smokers taking vitamin E or beta-carotene supplements should be studied further.
Some 29,000 people are diagnosed with cancer of the oral cavity or oropharynx in the United States each year. For more information about oral cancer detection, diagnosis and treatment, visit the National Cancer Institute Web site at "www.cancer.gov/cancertopics/wyntk/oral".© American Dental Association. All rights reserved. Reproduction or republication is strictly prohibited without the prior written permission from the American Dental Association.