Consuming starchy foods such as potatoes, tubers, roots, and refined grains may not significantly affect caries development, according to a longitudinal study recently published in the Journal of Public Health Dentistry.
Over 11 years, adults showed a minimal increase in decayed, missing, and filled teeth (DMFT), indicating no connection between starch intake and changes in caries, the authors wrote.
"Neither the amount nor the type of starch intake was associated with changes in dental caries over 11 years among Finnish adults," wrote the authors, led by F. H. Jangda of the Queen Mary University of London Institute of Dentistry in the United Kingdom (J Public Health Dent, November 16, 2024).
Starch itself is not fermentable by oral bacteria and poses no direct risk for dental caries. However, it is broken down into sugars by salivary amylase upon ingestion, raising questions about its potential link to caries, they wrote.
The study analyzed data from 2000-2011, focusing on 1,679 Finnish adults age 30 and older who participated in the Health 2000 survey and two follow-up surveys. Participants completed a validated 128-item food frequency questionnaire (FFQ) at baseline to estimate total daily starch intake (g/day and % of energy) and consumption of seven starch-rich food groups.
The FFQ evaluated habitual dietary intake over the past year, categorizing 128 foods and dishes into 12 sections, including dairy, cereals, vegetables, fruits, and beverages. Caries were assessed clinically using the DMFT score. Linear mixed-effects models evaluated the relationship between baseline starch intake and the 11-year change in DMFT scores, they wrote.
The mean DMFT score was 21.9 (95% confidence interval [CI], 21.6-22.2) at baseline in 2000, increasing by 0.47 (95% CI, 0.37-0.56) in 2004-2005 and an additional 0.33 (95% CI, 0.20-0.45) in 2011. The DMFT increase of 0.80 over 11 years represented a relatively slow rate of caries progression among adults.
Although total starch intake initially showed a positive association with baseline DMFT scores, regardless of whether it was measured in grams per day or as a percentage of energy intake, this association disappeared after covariate adjustment. Furthermore, no significant interaction was found between starch intake and time, they wrote.
However, the study had limitations. The sample size decreased due to follow-up losses and missing data. Participants who remained were generally younger, more educated, and healthier, limiting the generalizability of the findings, the authors added.
"This study found no association between the amount and type of starch intake and changes in dental caries among Finnish adults over an 11-year period," Jangda colleagues concluded.
