Sherry Torkos, BScPharm
If youre confused about GI or glycemic index, youre not alone. The idea of high-glycemic foods or low-glycemic foods is not necessarily intuitive. Sometimes our highs and lows can get mixed up; this article will help you understand how this index divides foods into different groups.
The glycemic index is a ranking of carbohydrates based on the rate they are broken down and subsequently affect blood glucose (sugar), the fuel used by the body’s cells for energy. Several factors influence the GI of a food, such as the type of starch or sugar it contains; the acid content; the amount of soluble fibre, which swells with water, slowing down the rate of digestion; and the extent of processing and cooking. Highly processed foods generally have a higher GI; for example, overcooking pasta increases the GI, compared to cooking it al dente.
High GI
Carbohydrates that are rapidly digested and broken down quickly into blood glucose are ranked as high GI. These include refined starches such as white bread and highly processed foods.
Eating high-GI foods can lead to blood sugar fluctuations (highs and lows), which may result in fatigue, increased appetite, and food cravings, particularly for sweets. Numerous studies have linked high-glycemic diets to obesity, insulin resistance, type 2 diabetes, high cholesterol, and increased risk of cardiovascular disease. There are also some studies that show high-GI diets increase the risk of certain cancers (breast, prostate, and colorectal).
Low GI
Carbohydrates that are more slowly digested and broken down into blood glucose have a low GI. Examples include most vegetables, some fruits, legumes, and unprocessed grains.
Several studies have shown that a low-glycemic diet can facilitate weight loss by helping the body burn fat more efficiently and curb appetite and cravings. Following a low-GI diet can help improve blood sugar control and improve insulin sensitivity. There are even benefits for the heart: low-GI diets have been shown to lower levels of triglycerides, cholesterol, and C-reactive protein–all known risk factors for heart disease.
Understanding the glycemic index and its relationship to your diet will help take a (GI) load off your mind when making the best food choices for you and your family.
GI Cheat Sheet
Here are some tips to help improve blood glucose control and lower the glycemic impact of your daily meals:
- Eat small frequent meals–three meals and two snacks daily.
- Have at least one low-GI food at each meal.
- Pair the good with the bad: combine a high-GI food with a low-GI food to reduce the overall glycemic impact of your meal.
- Choose smaller portions when eating high-GI foods.
- Avoid indulging in excessive amounts of low-GI foods simply because they are low GI. While certain foods register as low GI (ice cream, certain chocolate bars, french fries), they should be eaten in moderation as they are high in saturated fat and calories.
- Eat quality protein and healthy fats with your carbs to slow down the rate of digestion and reduce the glycemic impact of your meal.
- Eat sweets (desserts) after a meal when you will be full and satisfied with a smaller portion of a sweet, rather than as a separate snack. Having your sweets after a meal also impacts your blood sugar less than having it on its own.
- Add lemon or vinegar to your meals; these acidic ingredients can significantly lower the glycemic impact of your meal.
- Use natural, alternative sweeteners such as stevia to sweeten foods.
- Sprinkle cinnamon on your food; it helps improve insulin sensitivity and blood sugar control.
Sherry Torkos, BScPharm
Sherry Torkos, BSc Pharm, is a pharmacist and author of The Glycemic Index Made Simple (Wiley, 2007) and The Canadian Encyclopedia to Natural Medicine (Collins, 2013).
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