AIM:
The aim of the current study was to investigate the relationship between dietary intake, type of feeding during infancy, other lifestyle and sociodemographic factors, and dental caries.

DESIGN:
A cross-sectional study.

SETTING:
The study was carried out on children younger than 16 years of age who visited Primary Health Care Centers. The study was carried out over a period from October 2010 to June 2011 in Qatar.

PARTICIPANTS:
A random sample of 1752 children aged 6-15 years old who visited the Primary Health Care Centers was approached, and parents of 1284 children provided their consent and fulfilled the inclusion criteria (corresponding to a response rate of 73%).

METHODS:
The study was based on a questionnaire that included variables such as sociodemographic information, lifestyle, family history, and feeding patterns during infancy, information on oral hygiene practices, and clinical examination. The status of dental caries was recorded on the basis of the WHO criteria.

RESULTS:
The prevalence of dental caries [decayed, missed, or filled tooth (DMFT)] in the permanent dentition among children was 73% [95% confidence interval (CI): 71-75%], with a mean DMFT value of 4.5 (SD: 4.2). The numbers of children consuming sea food, cod liver oil, and vitamin-D-fortified milk less than once a week were significantly higher in the dental caries group compared with those without caries (11.7 vs. 8.3%; P=0.05, 92.4 vs. 87.5%; P=0.005, and 10.6 vs. 6.3%; P=0.011, respectively). Multivariable logistic regression analysis showed that being female [adjusted odds ratio (OR): 1.41; 95% CI: 1.07-1.84], having a BMI greater than the 95th percentile versus less than the 85th percentile (adjusted OR: 2.12; 95% CI: 1.17-3.84), a monthly household income of at least 10 000 QAR (adjusted OR: 2.61; 95% CI: 1.69-4.02), consumption of cod liver oil less than once a week (adjusted OR: 2.13; 95% CI: 1.35-3.37), 1-year increase in age (adjusted OR: 1.05; 95% CI: 1.01-1.11), being formula fed during infancy (adjusted OR: 2.27; 95% CI: 1.59-3.21), and frequency of tooth brushing once a day or less (adjusted OR: 1.36; 95% CI: 1.01-1.83) were associated independently with the risk of dental caries among children in Qatar.

CONCLUSION AND RECOMMENDATIONS:
Being female, overweight or obese, and monthly household income higher than US$2747 (≥10 000 QAR) were independent risk factors for dental caries. However, consumption of cod liver oil (at least once a week) and frequency of tooth brushing (more than once a day) were protective against dental caries. Health awareness and education on frequent tooth brushing, adequate nutrition, and obesity prevention should be promoted to avoid dental caries among children.