Vegetarianism and dental fluorosis among children in a high fluoride area of northern Tanzania

Abstract

Objective: The purpose of this study was to compare the prevalence and severity of dental fluorosis among vegetarian and nonvegetarian children and adolescents living in an area where dental fluorosis is endemic.

Design: An analytical cross-sectional retrospective study.

Sample and methods: Children (n = 165) aged 6-18 years, from five schools in Arusha town were examined. The children had a life-long exposure to drinking water with 3.6 mg F/litre. The severity of dental fluorosis was assessed using the Thylstrup & Fejerskov Index (TFI).

Results: In the vegetarian group (n = 24), the prevalence of dental fluorosis (TFI score > or = 1) was 67%, while 21% had severe fluorosis (TFI score > or = 5). In the nonvegetarian group (n = 141) the prevalence of fluorosis and severe fluorosis was 95% and 35%, respectively. In bi-variate correlation analyses age, vegetarianism and a series of other factors related to childhood nutrition (meals per day, the use of home-made porridge, the use of fish, etc.) were significantly associated with the tooth prevalence of dental fluorosis (TPF, P < 0.05). Stepwise multiple linear regression analyses explained 30% of the variance in TPF; age 15% points and vegetarianism 13% points. Multiple logistic regression analysis showed that the risk of developing dental fluorosis was seven times higher among nonvegetarians than among vegetarians.

Conclusion: The significantly lower prevalence and severity of dental fluorosis among the vegetarian group compared to the nonvegetarians would seem to be related to diet.