International tables of glycemic index and glycemic load values 2021: a systematic review.
Level 1 - systematic review of randomized trials
Systematic review of testing protocols across published and unpublished datasets
PubMed 34258626 · doi:10.1093/ajcn/nqab233
What was done
Systematic review (PROSPERO #171204) of published and unpublished sources compiling glycemic index (GI) and glycemic load (GL) data. Items were separated into two lists: precise values derived using International Standards Organization (ISO) methodology (~2100 items) and values determined using less robust methods, such as small sample sizes or large standard errors of the mean (~1900 items).
What was found
The database includes over 4000 food items (a 61% increase from the 2008 edition). Dairy products, legumes, pasta, and fruits were consistently low-GI (<=55 on the 100-point glucose scale) worldwide. Cereals and cereal products (including whole-grain/whole-meal versions), breads, breakfast cereals, rice, savory snacks, and regional foods showed wide variation across low, medium, and high GI values. Most potato varieties were high-GI, though specific low-GI varieties were identified.
Why it matters
Provides an expanded international reference database of GI and GL values to standardize carbohydrate quality assessments in clinical research, epidemiological studies, and dietary practice.
Limits
Abstract does not report the total number of studies or human subjects included. Approximately 1900 of the >4000 items rely on less robust methodologies with high measurement uncertainty, and many regional foods remain untested.
Cited by
- context On the glycemic index scale, broccoli has an index score of 1, whereas maltodextrin has a score over 100.
- supports Corn on the cob has a glycemic index of 51, while maltodextrin has a glycemic index over 100.
- context Non-starchy vegetables like broccoli, kale, and Brussels sprouts have less than one gram of starch and less than one gram of sugar per serving and a glycemic index of 1 or 2.
- supports Whole wheat flour is higher on the glycemic index and spikes blood sugar faster than table sugar.