Starch intake and changes in dental caries among adults: A longitudinal study in Finland.

Objective: To evaluate the association between starch intake (amount and type) and changes in dental caries among adults over 11 years.

Methods: Data from 1679 adults, aged 30 years and over, who participated in three consecutive surveys in Finland were pooled for analysis. Participants completed a validated semi-structured 128-item food frequency questionnaire at baseline, from which total starch intake (g/day and % energy intake) and the intake (g/day) of seven food groups high in starch (potatoes, potato products, roots and tubers, refined grains, pasta, wholegrains, and legumes) were estimated. Dental caries was determined during clinical examinations and summarized using the DMFT score, which was treated as a repeated outcome. The association between baseline starch intake and 11-year-change in DMFT score was tested in linear mixed-effects models adjusted for sociodemographic factors, behaviors, sugar intake, and health status.

Results: The mean DMFT score was 21.9 (95%CI: 21.6, 22.2) in 2000 (baseline), increasing by 0.47 (95% CI: 0.38, 0.56) in 2004/05, and additionally by 0.33 (95%CI: 0.20, 0.45) in 2011. Total starch intake was not associated with change in DMFT. This finding was similar irrespective of how starch intake was expressed (g/day or %EI). Of the seven food groups evaluated, only the intake of pasta was inversely associated with the DMFT score at baseline, but not with the change in DMFT over time.

Conclusion: Neither the amount nor the type of starch intake was associated with changes in dental caries over 11 years among Finnish adults.