Release Date: March 13, 1999
VANCOUVER, British Columbia -- Oral biologists from the University at Buffalo School of Dental Medicine have shown for the first time that heavy alcohol consumption or a diet low in antioxidant vitamins can increase the risk of developing gum disease.
The findings have implications beyond gum disease since bacteria from gum infections have been shown to play a role in heart disease, lung disease and diabetes, in addition to destroying gum tissue and bone.
Both studies were presented here today (March 13) at the combined meeting of the American Association for Dental Research and International Association for Dental Research.
The research was conducted in UB's Periodontal Disease Research Center, directed by Sara G. Grossi, D.D.S., senior research scientist. Both studies used data from the Third National Health and Nutrition Examination Survey (NHANES III), a population-based survey conducted in the U.S. from 1988-94.
For the alcohol/periodontal disease study, researchers analyzed data from 6,492 subjects between the ages of 20 and 90 selected randomly from the full sample. Persons who reported consuming alcohol from any source were divided into four groups based on consumption level, starting with five drinks per week or less and progressing to 20-per-week or more.
For periodontal-disease analysis, the subjects were divided into two groups based on attachment level, the amount of gum detachment from underlying bone.
Linking the data on alcohol consumption and attachment level showed a direct dose-response relationship between the amount of alcohol consumed weekly and severity of gum disease.
"As alcohol consumption increased from five drinks per week to 10, 15 and 20, the risk of periodontal disease rose from 10 percent to 20, 30 and then 40 percent," Grossi said. "When we see that kind of relationship, we know the findings are solid."
Grossi theorizes that alcohol may increase periodontal-disease risk in several ways: by decreasing the ability of neutrophils to fight infection; interfering with the clotting mechanism; decreasing the formation of new bone, and causing deficiencies in vitamin B complex and protein, components necessary for healing.
In a follow-up study, researchers will investigate the relationship of different types of alcohol and periodontal-disease risk.
In a related study, Grossi's team examined serum levels of antioxidant nutrients and their relationship to periodontal disease, using data from 9,862 subjects between the ages of 20 and 90 who participated in NHANES III.
To establish an antioxidant profile, researchers assessed levels of vitamins A, C and E; selenium; a-carotene; b-cryptoxanthin; lycopene, and lutein. Periodontal-disease status was established by combining mean gum-attachment level, plus the number and locations of detachments. The lowest and highest periodontal-disease groups then were compared with antioxidant status.
Results showed that selenium has the strongest association with gum disease, with low levels increasing the risk by 13 fold. Low levels of vitamins A and C, a-carotene and b-crytoxanthin also increased significantly the risk of gum disease. The only antioxidant studied in which low levels were protective was lutein; Grossi said the mechanism for this relationship remains unclear.
"Clearly, low levels of most antioxidants are a risk factor for periodontal disease and infection," she said. "Free radicals are released as a result of bacteria clearance and killing. Periodontal tissue depends on natural antioxidants to overcome this oxidative stress and maintain homeostasis. When antioxidants are depleted, the ability of gum tissue to overcome oxidative stress, maintain normal tissue and control the bacterial damage appears to be compromised."
More research is needed to sort out the mechanisms by which antioxidants are protective in periodontal tissue, and to conduct intervention studies to test the effects of antioxidants on gum tissues, she noted.
Additional researchers involved in the two studies were Mieko Nishida and Mine Tezal, students in oral biology; Alex W. Ho, statistician; Robert Dunford, senior programmer, and Robert J. Genco, D.D.S., Ph.D., SUNY Distinguished Professor and chair of the Department of Oral Biology.
Both studies were supported by grants from the U.S. Public Health Service, with additional support from Sunstar Inc. for the antioxidant study.