Researchers from Brigham Young University have created the first nationally-representative glycemic index database, breaking down the glycemic impact of foods commonly consumed by Americans. The findings were published in the American Journal of Clinical Nutrition.
 
Utilizing data from National Health and Nutrition Examination Surveys spanning 1999 to 2018, and covering nearly 50,000 participants, the AI-enabled database breaks down evolving dietary trends over time and how nearly 8,000 commonly-consumed foods impact one’s blood sugar.
 
Ultimately, the database is designed to help consumers determine the quality of their carbohydrates consumed, and improve awareness of the role of glycemic impact in health.
 
“The quality of carbohydrate intake, as measured by the glycemic index, has not been evaluated nationally over the past 2 decades in the United States,” the authors noted.
 
After amassing the NHANES data, an AI model matched glycemic index (GI) values from two GI databases to food codes from the U.S. Department of Agriculture, which were then manually verified.
 
In the data, which spanned 1999 to 2018, soft drinks and white bread were the top contributors to dietary GI and glycemic load (GL), with runners-up in both GI and GL including white bread, rice, pizza, fruit juice, and french fries.
 
 GI measures how quickly a food can cause your blood sugar to rise, while GL measures both the GI as well as how much glucose per serving a food delivers. Across all of the NHANES participants, the mean dietary GI was 55.7, and the energy adjusted GL was 133.
 
Over the course of the 19 years, dietary GI and GL decreased by 4.6% and 13.8%, respectively. Dietary GL tended to be higher among women than men, and was higher in those with less education and who were living under the poverty level. Differences in race were also observed. Additionally, as individuals aged, their GI and GL values decreased as a result of a tendency to make healthier carbohydrate choices. “Exploratory analyses revealed substantial differences for GI and GL across sex, race/ethnicity, education, and income levels, highlighting the importance of carbohydrate quality for population health outcomes in the United States,” the authors noted.
 
For the first time, dietary GI and GL from two large databases can now be successfully implemented into epidemiologic studies of multiple diverse populations, the authors concluded.
 
“The quality of carbohydrates and their nutritional classification continue to play a significant role in cardiometabolic disease development,” the authors concluded. “This study marks the creation of the first national GI database with associated dietary GI and GL derived from 10 cycles of nationally representative surveys in the United States. Our approach extends the applicability of description mapping and advances the methodology for incorporating GI and GL values into large-scale databases of diverse surveys and cohorts.’