Researchers Explore How Pure Cranberry Juice May Help Prevent Tooth Decay - Video

Could drinking pure cranberry juice help protect teeth from cavities and harmful plaque bacteria? A new study suggests that unsweetened cranberry juice may slow dental plaque growth and reduce acid production, potentially offering benefits for oral health in both children and adults.

Conducted by researchers at the University of Illinois Chicago (UIC) College of Dentistry, the study investigated how naturally occurring compounds in cranberries influence dental plaque bacteria responsible for tooth decay.

Cranberries contain proanthocyanidins, plant compounds known for their anti-inflammatory and antibacterial properties. These compounds can interfere with bacterial attachment to surfaces, potentially limiting harmful bacterial activity.

Dental plaque contains bacteria that metabolise dietary sugars and produce acids capable of damaging tooth enamel, eventually contributing to cavities.

To examine cranberry juice's effects, researchers recruited 22 participants, including 14 children and eight adults. Participants were randomly assigned to consume either unsweetened 100% cranberry juice, a cranberry juice cocktail containing 27% juice with added sugar, or water.

Researchers collected dental plaque samples before beverage consumption. Participants then consumed their assigned drinks in three small portions, briefly swishing each portion before swallowing.

Thirty minutes later, additional plaque samples were collected to assess changes in bacterial activity and acid production.

The findings revealed that plaque exposed to pure cranberry juice showed slower regrowth compared with samples collected before consumption.

Importantly, pure cranberry juice was also associated with reduced acid production in both children and adults, suggesting a possible protective effect against enamel damage.

Researchers suggested that cranberry-derived compounds may interfere with bacterial processes involved in plaque formation and acid generation.

However, the study involved a small number of participants and examined only short-term effects, making it difficult to determine whether regular cranberry juice consumption can prevent cavities. Further clinical studies are needed to confirm these findings and assess long-term benefits.

REFERENCE: Wu, C. D., et al. (2026). In vivo exposure to cranberry juice suppresses dental plaque regrowth and acid production in adults and children: A PGRM study. Scientific Reports. DOI: 10.1038/s41598-026-56025-3