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Dangerous sugar high

What is impaired glucose tolerance (IGT)?


People with IGT are not only at increased risk for type 2 diabetes, but are also 50% more likely to develop high blood pressure and high cholesterol levels – factors that contribute to heart disease and stroke.

A friend of mine has insulin resistance... is this the same as IGT?

No, not necessarily. Insulin resistance occurs when the body stops responding as well to insulin. To compensate, the body makes more insulin. But because the body doesn't respond as well to insulin, the higher insulin levels cannot control blood glucose as effectively. As insulin resistance increases, blood sugar levels will rise and diabetes can eventually result.

Who is at risk of developing IGT?

People that are extremely overweight or obese are at risk of developing IGT, especially those people carrying extra weight around their middle. This is because carrying extra body fat inhibits the effects of insulin. With weight loss, glucose levels will likely return to normal levels. Because there is less resistance to insulin, more glucose is transported from the blood into tissue cells. Losing weight will also help reduce the risk of developing type 2 diabetes.

Your risk of developing IGT and type 2 diabetes also increases if you are physically inactive, have a family history of diabetes, have had gestational diabetes (i.e. having diabetes while pregnant), gave birth to a baby that weighed more than nine pounds at birth, are of Native, Hispanic, Asian, African, or Pacific Island descent, have a condition called polycystic ovary syndrome, or regularly sleep less than 6 hours or more than 9 hours per day.

Know your numbers

What are the signs and symptoms?

People with imparied glucose tolerance (IGT) often have no symptoms. In fact, millions of people have diabetes and don't know it because symptoms develop so gradually, people often don't recognize them. Symptoms of diabetes include the following:

  • frequent urination
  • constant thirst
  • always being tired
  • blurred vision
  • cuts and bruises that are slow to heal
  • frequent infections
  • tingling or numbness in your hands or feet

How is IGT diagnosed?

IGT is diagnosed using the oral glucose tolerance test. After fasting for at least 8 hours, a person's blood glucose is measured before and 2 hours after drinking a glucose-containing solution solution containing 75 grams of glucose.


How often should I be tested?




Take control!

What to do if you have IGT







You can help manage your condition with these nutrition tips.




High-sugar foods Low-sugar or sugar-free alternatives
Sugar, syrup, glucose, dextrose Artificial sweeteners
Jam, marmalade Low-sugar jam and marmalade
Puddings or canned fruit in syrup Low-sugar or diet yogurt

Increase your intake of fruits and vegetables. It's easier than you think to eat 7 to 10 servings! Enjoy fruit for snacks, and add vegetables to make your favourite meals even tastier.

Limit fried and fatty foods. Choose low-fat dairy products, lean meats and poultry; grill, barbecue or oven-bake your meat instead of frying; and cook with moderate amounts of unsaturated oils such as olive, sunflower or corn oil.

If you drink alcohol, drink in moderation. This means:



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