April 20, 2024 The glycemic index (GI)

Diabetes Canada recommends people with type 1, type 2, or pre-diabetes choose lower glycemic index (GI) foods and drinks more often to help control blood sugar. The GI is a scale out of 100 that ranks a carbohydrate-containing food or drink by how much it raises your blood sugar levels after it is eaten or drank.

Foods with a high GI increase blood sugar higher and faster than foods with a low GI. There are three GI categories:

• low GI (55 or less) 
• medium GI (56-69)
• high GI (70 or more)

Eat foods in the low GI category most often, the medium category less often, and eat foods in the high GI category the least often. Work with your Registered Dietitian to find ways to substitute high GI foods for foods in the medium and/or low GI category.

In general, the more highly processed a food is, or the quicker a food is digested, the higher the GI. For example, instant oats have a higher GI than steel cut oats. 

Benefits of a low glycemic index diet

A low GI diet can help you:

• decrease risk of type 2 diabetes and its complications
• decrease risk of heart disease and stroke
• feel full longer
• maintain or lose weight

Meal planning ideas

Try these meal planning ideas to lower the GI of your meal:

Cook your pasta al dente (firm) so that your body has to work more to digest and absorb nutrients. Since al dente pasta requires more work from the body during digestion, the digestion rate is slower and, therefore, the GI is lower. Check your pasta package instructions for cooking time. 

Make fruits and milk part of your meal. These foods often have a low GI and make a healthy dessert. 

Try lower GI grains such as barley, bulgur and pulses (such as beans, lentils, and chickpeas). To get started, try swapping half of your higher GI grain/starch food serving with pulses. For example, instead of having one cup of cooked short grain rice, have ½ cup of cooked rice mixed with ½ cup of black beans.

Using the glycemic index to choose foods is just one aspect of healthy eating. Healthy eating also means choosing a variety of foods, having moderate portion sizes, and selecting more whole foods instead of processed foods.

Checking your blood sugar before, and two hours after a meal is the best way to know how your body handles certain foods and drinks.

Low GI foods (choose most often)

Low GI grains & starches:

Breads

• Heavy mixed grain
• Spelt
• Sourdough bread
• Tortilla (whole grain)

Cereal

• All Bran™
• Bran Buds with Psyllium™
• Oat Bran™
• Oats (steel cut)

Grains

• Barley
• Bulgur
• Mung bean noodles
• Pasta (al dente, firm)
• Pulse flours
• Quinoa
• Rice (parboiled, converted)

Other starches

• Peas
• Popcorn
• Sweet potato
• Winter squash

Low GI fruits

• Apple
• Apricot (fresh, dried)
• Banana (green, unripe)
• Berries
• Cantaloupe
• Grapefruit
• Honeydew melon
• Mango
• Orange
• Peach
• Pear
• Plum
• Pomegranate
• Prunes

Low GI milk, alternatives & other beverages

• Milk (almond; cow – skim, 1%, 2%, whole; soy) 
• Yogurt (skim, 1%, 2%, whole; Frozen, Greek)

Low GI meat & alternatives

• Baked beans
• Chickpeas
• Kidney
• Mung
• Romano beans; lentils, soybeans/edamame, split peas

(Meat, poultry, and fish do not have a GI becuase they do not contain carbohydrate.)

Medium GI foods (choose less often)

*Most starchy/sweet vegetables (e.g. peas, parsnip, winter squash) provide 15 g or more carbohydrate per 1 cup serving. Beets and carrots often provide less than 15 g carbohydrate per serving (marked below with *).

Medium GI grains & starches:

Breads

• Chapati, pita, roti (white, whole wheat)
• Flaxseed or linseed bread
• Pumpernickel, rye, stone ground whole wheat, whole grain wheat bread

Cereal

• Cream of Wheat™ (regular)
• Oats (instant, large flake, and quick)

Grains

• Basmati, brown, short or long grain white, and wild rice
• Cornmeal
• Couscous
• Rice noodles

Other starches

• Beets*
• Corn
• Parsnip
• Potato (red, white, cooled)
• Rye crisp (Ryvita™)
• Stoned Wheat Thins™ crackers

Medium GI fruits

• Banana (ripe, yellow)
• Cherries
• Cranberries (dried)
• Figs (fresh, dried)
• Grapes
• Kiwi
• Lychee
• Pineapple
• Raisins

Medium GI meat & alternatives

Lentil and split pea soup (ready-made)

High GI foods (choose least often)

*Most starchy/sweet vegetables (e.g. peas, parsnip, winter squash) provide 15 g or more carbohydrate per 1 cup serving. Beets and carrots often provide less than 15 g carbohydrate per serving (marked below with *).

High GI grains & starches:

Bread

• Bread (white, whole wheat)
• Naan (white, whole wheat)

Cereal

• All-Bran Flakes™
• Corn Flakes™
• Cream of Wheat™ (instant)
• Puffed wheat
• Rice Krispies™
• Special K™

Grains

Jasmine, sticky, or instant white rice; millet

Other starches

• Carrots*
• Potato (instant mashed; red, white, hot)
• Pretzels
• Rice cakes
• Soda crackers

High GI fruits

• Banana (brown, overripe)
• Watermelon

High GI milks, alternatives & other beverages

Rice milk