1, Acidic substances: morinda citrifolia juice is an acidic beverage. Drinking it for a long time or in excess will lead to imbalance of acid-base balance in the oral cavity, which will lead to whitish tongue coating.

2. Food residue: After drinking morinda citrifolia juice, the fructose in it will remain in the mouth, and it will combine with bacteria in the mouth to form acidic substances, which will lead to whitish tongue coating.

3. Oral inflammation: Excessive drinking of morinda citrifolia juice will stimulate oral mucosa, cause oral inflammation, and then lead to whitish tongue coating.