There is limited research on carbohydrate intake and oral microbiome diversity and composition assessed with next-generation sequencing. Our goal was to better understand the association between habitual carbohydrate intake and the oral microbiome, as the oral microbiome has been associated with caries, periodontal disease, and systemic diseases. We investigated whether total carbohydrates, starch, monosaccharides, disaccharides, fiber or glycemic load (GL) were associated with the diversity and composition of oral bacteria in subgingival plaque samples from 1204 postmenopausal women .
Carbohydrate intake and glycemic load (GL) were assessed from a food frequency questionnaire and adjusted for energy intake. The V3–V4 region of the 16S rRNA gene was sequenced from subgingival plaque samples to identify relative abundance of microbiome composition data expressed as operational taxonomic units (OTUs). OTU abundance was centered on the log(2) transformed ratio to account for the compositional data structure. Associations between carbohydrate/GL intake and measures of microbiome alpha diversity were examined using linear regression. PERMANOVA analyzes were performed to examine measures of microbiome beta diversity across carbohydrate/GL intake quartiles. Associations between carbohydrate intake and GL and the abundance of the 245 identified OTUs were examined using linear regression. Total carbohydrate, GL, starch, lactose, and sucrose intake were inversely associated with alpha diversity measures. Beta diversity in the quartiles of total carbohydrate, fiber, GL, sucrose, and galactose were all statistically significant (p for PERMANOVA p < 0.05).
Positive associations were observed between total carbohydrates, GL, sucrose and Streptococcus mutans; GL and Sphingomonas HOT 006 and Scardovia wiggsiae; and sucrose and Streptococcus lactarius. A negative association was observed between lactose and Aggregatibacter segnis, and between sucrose and TM7 [G-1] HOT 346 and Leptotrichia HOT 223. The intake of total carbohydrates, GL and sucrose was inversely associated with the alpha diversity of subgingival bacteria , microbiota beta diversity varied depending on intake, and was associated with the relative abundance of specific OTUs. Higher intake of sucrose, or foods high in GL, may influence poor oral health outcomes (and perhaps systemic health outcomes) in older women through its influence on the oral microbiome.
The foods we eat regularly influence the composition of bacteria, both good and bad, in our mouth. And researchers are finding that this collective of bacteria known as the oral microbiome likely plays an important role in our overall health, in addition to its previously known associations with tooth decay and periodontal disease.
Scientists at the University at Buffalo have shown how consuming certain types of foods affects the oral microbiome of postmenopausal women. They found that higher intakes of sugary and high-glycemic foods, such as donuts and other baked goods, regular soft drinks, breads, and nonfat yogurts, may influence poor oral health and, perhaps, systemic health outcomes in older women due to the influence that these foods have on the oral microbiome.
In a study in Scientific Reports, an open access journal from the editors of Nature, the UB-led team investigated whether carbohydrates and sucrose, or table sugar, were associated with the diversity and composition of oral bacteria in a sample of 1204 postmenopausal women using data from the Women’s Health Initiative.
It is the first study to examine carbohydrate intake and the subgingival microbiome in a sample composed exclusively of postmenopausal women. The study was unique in that the samples were taken from subgingival plaque, which is located under the gums, rather than salivary bacteria.
"This is important because the oral bacteria involved in periodontal disease reside primarily in subgingival plaque," said the study’s first author, Amy Millen, PhD, associate professor of epidemiology and environmental health in the School of Public Health and Professions. UB Health.
"Looking at measurements of salivary bacteria may not tell us how oral bacteria are related to periodontal disease because we are not looking at the right environment inside the mouth," he added.
The research team reported positive associations between total carbohydrates, glycemic load and sucrose and Streptococcus mutans, a contributor to dental caries and some types of cardiovascular diseases, a finding that confirms previous observations. But they also observed associations between carbohydrates and the oral microbiome that are not as well established.
The researchers noted that Leptotrichia spp., which has been associated with gingivitis, a common gum disease, was positively associated with sugar intake in some studies. The other bacteria they identified as being associated with carbohydrate intake or glycemic load had not previously been appreciated as contributing to periodontal disease in the literature or in this cohort of women, according to Millen.
"We examined these bacteria in relation to habitual carbohydrate intake in postmenopausal women across a wide variety of carbohydrate types: total carbohydrate intake, fiber intake, disaccharide intake, simple sugar intake," Millen said. "No other study has examined oral bacteria in relation to such a wide variety of carbohydrate types in a cohort. We also looked at associations with glycemic load, which is not well studied in relation to the oral microbiome."
The key question now is what all this means for overall health, and that’s not so easy to understand yet.
"As more studies are conducted looking at the oral microbiome using similar sequencing techniques and the progression or development of periodontal disease over time, we could begin to make better inferences about how diet relates to the oral microbiome and periodontal disease," Millen said.
Source: Amy E. Millen, Runda Dahhan, Jo L. Freudenheim, Kathleen M. Hovey, Lu Li, Daniel I. McSkimming, Chris A. Andrews, Michael J. Buck, Michael J. LaMonte, Keith L. Kirkwood, Yijun Sun , Vijaya Murugaiyan, Maria Tsompana, Jean Wactawski-Wende. Dietary carbohydrate intake is associated with the subgingival plaque oral microbiome abundance and diversity in a cohort of postmenopausal women. Scientific Reports, 2022; 12 (1) DOI: 10.1038/s41598-022-06421-2
