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A 2015 study by Park Yong Deok, a Kyung Hee University’s Graduate School of Dentistry professor, examined how certain foods contribute to tooth discoloration. The research surveyed 300 young professionals on their perceptions of stain-causing foods and analyzed the staining potential of 19 commonly consumed items.
Tooth discoloration can result from external factors like diet, smoking, poor oral hygiene, or internal factors. The team tested these foods using tooth-like discs and scored them from 1 to 16. Higher scores indicated more severe staining.
The findings revealed unexpected results, with some everyday foods ranking surprisingly high. Black tea emerged as the worst offender, scoring 12.7 points.
Chocolate came in second place, scoring over 10 points. Its dark pigments and sticky texture significantly contributed to its staining effect.
Third place went to kimchi stew, a popular Korean dish, scoring 10.6 points. While plain kimchi scored low at 2 points, the stew’s added fatty ingredients significantly boosted its staining potential.
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Black tea’s top ranking was attributed to its high tannin content and strong pigments. Using black tea as a benchmark, the study found that chocolate and Americano coffee scored in the 80s, while kimchi stew scored in the 70s on a relative staining index.
Surprisingly, cola scored only 2 points for direct staining. However, experts cautioned that its acidity could erode enamel, indirectly making teeth appear yellower over time.
Curry scored a low 2.3 points, showing minimal staining effects. Its score increased slightly when paired with coffee, but its self-cleaning properties helped minimize discoloration.
The study emphasized the importance of oral hygiene in preventing stains. Brushing immediately after consuming pigment-rich foods like black tea or chocolate is ideal, but even rinsing with water can reduce staining. Professional whitening treatments are an option for noticeable discoloration, though prevention remains the best approach.
The results highlight the importance of maintaining good oral hygiene after meals to prevent staining from foods like black tea, chocolate, and stews. Dental health goes beyond aesthetics and is critical to overall oral well-being. Simple steps, such as rinsing your mouth or brushing after meals, can help keep your teeth healthy and your smile bright.
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