Researchers studied 380 preschool children in China to understand how tooth decay affects their growth and nutrition. They found that nearly 6 out of 10 children had cavities in their baby teeth. Kids with more cavities were more likely to be underweight or shorter than expected for their age. The good news? Simple habits like brushing teeth before bed, using fluoride toothpaste, visiting the dentist yearly, and limiting sugary foods can prevent cavities and help kids grow better. Parents who knew more about dental health had children with fewer cavities.

The Quick Take

  • What they studied: Whether tooth decay in young children is connected to how well they grow and their overall nutrition
  • Who participated: 380 children between ages 3-6 years old from 15 kindergartens in Shijiazhuang, China. The group included both boys and girls from different backgrounds.
  • Key finding: About 59% of the children had cavities in their baby teeth. Children with more cavities were noticeably shorter and weighed less than children without cavities. Kids who brushed their teeth before bed had 78% fewer cavities, and those using fluoride toothpaste had 96% fewer cavities.
  • What it means for you: If your child has cavities, it may be a sign to check their growth and nutrition. Simple preventive steps—especially bedtime brushing with fluoride toothpaste and limiting sweets—can protect both their teeth and their overall health. However, this study shows a connection, not necessarily that cavities cause growth problems.

The Research Details

Researchers took a snapshot in time, looking at 380 children all at once rather than following them over months or years. They measured each child’s height and weight using standard methods, checked their teeth for cavities, and asked parents questions about their child’s diet, brushing habits, and dental care. They used a special scoring system to count how many teeth were decayed, missing, or filled. The researchers then looked for patterns—did children with cavities tend to be shorter or lighter than those without cavities?

The children were selected from 15 different kindergartens using a method that helps ensure the group represents the broader population. Researchers used statistical tests to figure out which habits and parental knowledge made cavities more or less likely. They also measured how strongly cavity numbers connected to weight-for-height measurements, which show if a child is getting enough nutrition right now.

This type of study is useful for spotting connections between different health problems in a population. By looking at many children at once, researchers can identify patterns that might need further investigation. The study is particularly valuable because it looks at modifiable factors—things parents can actually change, like brushing habits and diet—rather than just unchangeable characteristics.

This study has several strengths: it included a reasonably large group of 380 children, used standard international methods for measuring cavities and growth, and looked at multiple factors at once. However, because it’s a snapshot rather than following children over time, we can’t be completely sure that cavities cause growth problems—they might just happen together. The study was conducted in one Chinese city, so results might differ in other places with different diets, water fluoridation, or healthcare access. The researchers did adjust their analysis for multiple factors, which strengthens the findings.

What the Results Show

Nearly 6 out of 10 children (59%) had cavities in their baby teeth, with an average of 2-3 decayed, missing, or filled teeth per child. This rate was similar for boys and girls and didn’t change much between ages 3 and 6.

Children with cavities were significantly more likely to be shorter than normal for their age, weigh less than normal, or weigh less relative to their height. The more cavities a child had, the lower their weight-for-height score, suggesting a strong connection between cavity severity and current nutritional status.

Several habits and factors strongly protected against cavities: brushing teeth before bed reduced cavity risk by 78%, using fluoride toothpaste reduced it by 96%, having annual dental check-ups reduced it by 74%, taking vitamin D supplements for 2+ years reduced it by 60%, and parents having good dental knowledge reduced it by 62%. In contrast, eating sweet foods frequently increased cavity risk by 72%.

The study found no significant differences in cavity rates between boys and girls, or between younger (3-4 years) and older (5-6 years) children, suggesting cavity problems affect this age group broadly. The strong connection between cavity count and weight-for-height measurements was particularly notable, with a correlation of -0.649 (meaning more cavities strongly predicted lower weight-for-height). Parental oral health knowledge emerged as an important protective factor, suggesting that education matters.

The 59% cavity rate in this study is consistent with other research showing that early childhood cavities are very common in many parts of the world, particularly in developing regions. The protective effects of fluoride toothpaste and regular dental visits align with decades of dental research. The connection between cavities and growth is less commonly studied but fits with existing evidence that oral health and overall nutrition are interconnected. The strong protective effect of bedtime brushing is particularly notable and reinforces dental health guidelines.

This study shows connections but cannot prove that cavities cause growth problems—they might both result from poor nutrition or other shared factors. The study was conducted in one Chinese city, so results may not apply to other regions with different water fluoridation, dietary patterns, or healthcare systems. The researchers relied on parents to report some information, which might not always be completely accurate. The study didn’t measure some factors that could matter, like family income or access to healthcare. Finally, because this is a single snapshot in time, we don’t know if the growth differences came before or after the cavities developed.

The Bottom Line

Parents should establish a bedtime tooth-brushing routine using fluoride toothpaste starting as early as possible—this showed the strongest protective effect. Limit sugary foods and drinks, especially between meals. Schedule annual dental check-ups for children starting around age 1-2. Consider vitamin D supplementation if recommended by your pediatrician. Learn about proper dental care for young children and share this knowledge with caregivers. These recommendations have strong evidence support from this and other studies.

All parents and caregivers of young children (ages 3-6) should pay attention to these findings. This is especially important for families in areas without water fluoridation or limited dental care access. If your child has cavities, discuss with your pediatrician whether growth or nutrition issues might also need attention. Children with signs of poor growth (being much shorter or lighter than peers) should have both dental and nutritional evaluation.

Cavity prevention is an ongoing process—you should see fewer new cavities within 6-12 months of establishing good brushing habits. Growth improvements from better nutrition and oral health typically take several months to become noticeable, as children grow gradually. Annual dental check-ups help catch problems early before they become severe.

Want to Apply This Research?

  • Track daily bedtime tooth-brushing completion and weekly sugary snack/drink frequency. Set a goal of 7/7 days brushing and limiting sugary items to 2 or fewer times per week. Monitor child’s height and weight monthly, comparing to growth charts.
  • Use the app to set a daily bedtime brushing reminder with your child’s favorite character or reward system. Create a weekly ‘sugar-free snack’ challenge where you log healthy alternatives to sweets. Schedule and receive reminders for annual dental appointments.
  • Log brushing habits daily, dietary choices weekly, and growth measurements monthly. Track cavity-related dental visits and any new cavities found at check-ups. Monitor for signs of poor growth (clothes fitting differently, child seeming smaller than peers) and share data with pediatrician at regular visits.

This research shows a connection between cavities and growth in young children but does not prove that cavities directly cause growth problems. The study was conducted in China and results may vary in other populations. This information is for educational purposes and should not replace professional medical or dental advice. If you have concerns about your child’s dental health, growth, or nutrition, consult with your pediatrician or pediatric dentist. Always follow your healthcare provider’s specific recommendations for your child’s individual needs.