Green tea good for oral health
Drinking at least three cups of green tea per day may promote a good oral health-related quality of life (OHRQoL), as suggested in a study from Japan.
The study included 7,514 Japanese aged ≥65 years (52.6 percent female). All participants completed a validated self-administered questionnaire that included items on the frequency of consumption of green tea and coffee. They also reported their OHRQoL using the General Oral Health Assessment Index (GOHAI), which evaluates oral health-related problems affecting well-being.
GOHAI included items grouped into functional factors (eating, speaking and swallowing), psychosocial factors (concerns, relation discomfort and appearance) and experience of pain or discomfort (drugs, gum sensitivity and discomfort when chewing certain foods). Poor OHRQoL was defined as GOHAI score of <50 points.
Results showed that increased consumption of green tea was associated with a higher GOHAI score in both men and women (ptrend<0.001). The respective multivariate odds ratios for a poor OHRQoL associated intake frequencies of <1, 1–2 and ≥3 cups/day vs none were 1.01 (95 percent CI, 0.80–1.27), 0.95 (0.74–1.21) and 0.78 (0.61–0.99; ptrend=0.024) in men; and 1.19 (0.90–1.57), 0.98 (0.74–1.29) and 0.86 (0.67–1.12; ptrend=0.014) in women.
On the other hand, there was no statistically significant association observed between coffee intake and GOHAI score in men (ptrend=0.538) or women (ptrend=0.607).
Green tea is a rich dietary source of polyphenols, including catechins, particularly epigallocatechin-3-gallate. It is said that catechins inhibit acid production by oral bacteria and exert bactericidal activity against P. gingivalis. Meanwhile, a lower risk of tooth loss and periodontal disease translates to improved OHRQoL. [Caries Res 2007;41:342-349; Health Qual Life Outcomes 2010;8:126]
Therefore, the positive impact of green tea on OHRQoL may be attributed to catechins, researchers said.