UGA Extension contacts:
Elizabeth Kindamo and Alison Berg

Additional authors include Candace Tucker, MS, NDTR; and Hannah Wilson, PhD, RDN, LD.

Glycemic Index

The glycemic index (GI) tells you how carbohydrate foods raise blood glucose compared to either glucose alone or white bread.

  • Glycemic index ranges from 0 to 100, where 100 is pure glucose (sugar).
  • GI is based on 50 g of carbohydrates from each food.
  • The lower a food’s GI, the slower blood sugar rises after eating that food.
  • The higher a food’s GI, the quicker blood sugar rises after eating that food.
  • Glycemic index considers effects of the carbohydrate content of food but not the overall nutritional value of a food.
  • GI is determined using reference lists, charts, or books. An individual cannot calculate a glycemic index independently.
Glycemic index (GI) level of a food Assigned GI value
Low GI 55 or less
Medium GI 56 to 69
High GI 70 or higher

Research is mixed on whether choosing foods based on their glycemic index helps control your blood sugar over time. Speak with your healthcare provider to determine if and how you should use glycemic index to manage your blood glucose.

Glycemic Index (GI) of Select Common Foods
Food GI value
100% whole grain bread 51
Apple 39
Baked beans 40
Baked russet potato 111
Banana, ripe 62
Brown rice 50
Carrots 35
Corn tortilla 52
Grapes 59
Green peas 51
Ice cream, regular 57
Instant oatmeal 83
Macaroni  47
Microwave popcorn, plain 55
Milk, full fat 41
Milk, skim 32
Oatmeal 55
Orange 40
Peach 42
Peanuts 7
Raisins 64

Spaghetti, white, boiled

58
Sweet potato 70
Watermelon 72
Wheat tortilla 30
White bagel 72
White pita bread 68
White rice 89
White wheat flour bread 71
Whole wheat bread 71

Glycemic Load

Glycemic load (GL) takes into account the GI of a food and how much of that food you eat (planned portion size). GL can be calculated for any size serving of a single food, a mixed meal of several foods, or an entire day’s meals.

Glycemic load = (carbohydrate content in grams x GI) / 100

Glycemic load (GL) level Assigned GL value
Low GL 10 or less
Medium GL 11 to 19
High GL 20 or higher

References

American Diabetes Association Professional Practice Committee. (2024). Facilitating positive health behaviors and well-being to improve health outcomes: Standards of care in diabetes. Diabetes Care, 47(Supplement_1), S77–S110. https://doi.org/10.2337/dc24-S005

Atkinson, F. S., Foster-Powell, K., & Brand-Miller, J. C. (2008). International tables of glycemic index and glycemic load values. Diabetes Care, 31(12), 2281–2283. https://doi.org/10.2337/dc08-1239


Published by University of Georgia Cooperative Extension. For more information or guidance, contact your local Extension office.

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