(P21-010-25) Linking Habitual Carbohydrate Intake Patterns to Postprandial Glucose Dynamics, Metabolic and Lipidomic Profiles: The Carbotype Concept

Objectives: This study aimed to characterize habitual carbohydrate intake patterns, termed “Carbotypes,” and examine their relationships with postprandial glucose responses to high-carbohydrate food groups, metabolomic and lipidomic profiles, and clinical biomarkers.

Methods: Dietary records were collected from 71 healthy adults (52.1y; 13 d/participant). The proportional contribution of daily carbohydrate intake from each food group relative to total daily carbohydrate intake was calculated. Participants were classified into distinct carbotypes based on carbohydrate-contributing dietary features using k-means clustering. Plasma samples were analyzed for metabolome (n=731) and lipidome (n=655) using mass spectrometry, and postprandial glucose dynamics were measured via continuous glucose monitoring.

Results: Two distinct carbotypes were identified, with non-different intakes in total carbohydrate and total and saturated fats between clusters. Cluster 1 consumed carbohydrates mainly from fruits (14%), non-starchy vegetables (10%), and sweets (8%), whereas Cluster 2 consumed carbohydrates from sweets (20%), bread products (12%), and fruits (7%). Linear regression analyses, controlling for age, sex, ethnicity, BMI, and total fat, revealed higher total cholesterol, triglycerides, and LDL in Cluster 2 (P_BH < 0.05), with no differences in glucose markers including A1C. Interestingly, individuals with high habitual bread consumption exhibited higher postprandial glucose responses (AUC above baseline) to standardized bread consumption (P <0.1). Lipidomics analyses further distinguished carbotypes: Cluster 1 showed higher levels in 10 free fatty acids, phosphatidylcholine, and triacylglycerol species, while Cluster 2 had 8 higher triacylglycerols (|Log2 fold change|>1 and P<sub>BH < 0.1) in a volcano plot. Overall, 346 lipid species were different between carbotypes (P_BH < 0.05).

Conclusions: This study demonstrated that carbohydrate source composition significantly impacts lipidomic profiles and postprandial glucose dynamics. These findings highlight the need for personalized dietary strategies based on their habitual diet patterns to optimize lipid and glucose metabolism.

Funding Sources: This study was funded by the National Institutes of Health, American Diabetes Association, and Stanford University.