What Is the Glycemic Index?
The glycemic index (GI) is a measure of how quickly a food causes blood sugar levels to rise.
|Index Ranks Foods||Ranges (Scale of 0 to 100)|
|Low (good)||55 or Less|
|Medium||56 to 69|
|High (bad)||70 or Higher|
Foods with a high glycemic index are quickly digested and absorbed, causing a rapid rise in blood sugar while foods with a low GI are digested and absorbed at a slower rate, resulting in a slower rise in blood sugar levels.
High glycemic foods tend to be those high in processed carbohydrates and sugars while low GI foods tend to be rich in fiber, protein, and/or fat.
A criticism of the index is that it is based on the consumption of foods by themselves, on an empty stomach, and it does not take into account that most people consume a variety of foods in a meal, which can affect digestion and absorption.
What Is the Glycemic Index Used For?
There are a number of reasons people may want to consider the glycemic index of the foods they eat.
- It may help with weight loss
- May help with blood sugar control in people with type 2 diabetes
- Some studies have shown high GI diets are associated with higher risk for heart disease and stroke
- Two studies found a higher GI diet to be associated with significantly increased risk of developing gallstones (more study is needed)
What Is a Low Glycemic Food?
To consume a low glycemic index diet:
- Eat plenty of whole grains, nuts, legumes, fruit, and non-starchy vegetables
- Avoid potatoes, white rice, white bread, and sugary foods like cookies, cakes, candy, and soft drinks
Low glycemic foods tend to be rich in fiber, protein, and/or fat. Examples of foods that have a low GI (55 or less) include:
- Sweet corn (52)
- Banana, raw (51)
- Mango, raw (51)
- Orange juice (50)
- Brown rice, boiled (50)
- Strawberry jam/jelly (49)
- Vegetable soup (48)
- Corn tortilla (46)
- Spaghetti, white, boiled (46)
- Whole-grain pumpernickel bread (46)
- Orange, raw (43)
- Peaches, canned (43)
- Dates, raw (42)
- Apple juice (41)
- Yogurt, fruit (41)
- Carrots, boiled (39)
- Milk, full fat (39)
- Pear, raw (38)
- Milk, skim (37)
- Apple, raw (36)
- Soy milk (34)
- Lentils (32)
- Barley (28)
- Chickpeas (28)
- Cashews (25)
- Kidney beans (24)
- Peanuts (18)
- Soybeans (16)