Associations Between Diet Quality and Dental Caries in Low-Income Women

The Healthy Eating Index 2015 (HEI-2015) is a diet quality measure of conformity of diet to the 2015-2020 Dietary Guidelines for Americans. This tool is being used increasingly to assess relationships between diet quality and health outcomes.

The objective of this research was to investigate the relationships between diet quality as measured by HEI-2015 total and component scores and Decayed, Missing, Filled Teeth Index (DMFT) scores in low-income women.

In this cross-sectional study, low-income women were administered questionnaires and dental examinations on 1 occasion. The questionnaires included demographics, food frequency, and oral health questionnaires, and the US Adult Food Security Survey Module.

Participants in this study were part of a larger research project-Impact of Diet and Nutrition on Dental Caries in Low-Income Women. For the larger research project, a total of 255 women aged 18 to 50 years with annual income <250% of the Federal Poverty Line were recruited from low-income housing units in Central Texas from June 1, 2018 to December 30, 2018. Of the 255 women, 28 underwent dental screenings but did not complete the questionnaires. Seven women were excluded because energy intakes exceeded 4,000 kcal/d. The final sample for the current analysis was 220 women who had completed their dental examinations and provided complete data.

The exposure was diet quality and the main outcome measure was DMFT score.

Dental caries scores were calculated by addition of decayed, missing, and filled teeth. Descriptive statistics were conducted on the variables of age, race and ethnicity, education, annual household income, food security status, and frequency of brushing and flossing. Linear regression analysis was used to discern relationships between diet quality-as assessed by HEI-2015 total and component scores-and dental caries experience, adjusting for the covariates.

Caries in permanent teeth was present in 95.6% of participants. HEI-2015 total scores were inversely associated with dental caries. An increase of 1 point in total HEI-2015 score was accompanied by a decrease in DMFT score by 0.569 (P = .001). In addition, component scores for total vegetables (P = .001), greens and beans (P = .002), dairy (P = .004), refined grains (P = .001), and added sugars (P = .001) were inversely related to DMFT scores.

This research suggests that diet quality, as measured by the HEI-2015, is inversely associated with DMFT scores in low-income women. Future research is needed to investigate the influence of diet and nutrition on the integrity of oral health.