Diabetes and Carbohydrates

If you have diabetes, you can still eat foods that contain carbohydrates! Having diabetes means managing the type and amount of carbohydrates you eat. Read on to find out more about carbohydrates and how they affect people with diabetes.

What is a carbohydrate?

A carbohydrate is a nutrient that provides you with calories (energy) and affects your blood sugar (or blood glucose). The following foods contain carbohydrates:

  • Vegetables and Fruit: Starchy vegetables like potatoes, cassava, yams, corn and peas have higher amounts of carbohydrates. Other vegetables have small amounts of carbohydrates in them. All fruit including fresh, frozen, canned, dried and fruit juice contain carbohydrates.
  • Grain Products: Rice, pasta, breads, crackers and cereal are examples of grains that contain carbohydrates.
  • Milk and Alternatives: Milk, yogurt and soy beverages contain carbohydrates.
  • Meat Alternatives: Beans, lentils and dried peas have carbohydrates.

Carbohydrates are also found in snack foods like baked goods, ice cream, chocolate, pop, candy, pretzels, tortillas and chips. 

How do carbohydrates affect people with diabetes? 

When we eat, carbohydrates in food are digested and turned into sugar or glucose. Glucose then gets absorbed into our blood. The glucose goes from our blood into our cells with help from a hormone called insulin (insulin is made in the pancreas). We then use the glucose in our cells for energy.  If you have Type 2 diabetes, your body cannot move glucose from your blood into your cells well. This may happen because:

  • your pancreas cannot make any insulin or enough insulin
  • your cells resist the insulin and glucose cannot enter your cells

When glucose cannot go into your cells, it stays in the blood causing high blood glucose levels or “high blood sugar.” Not managing high blood glucose can cause health problems

Carbohydrate breakdown: What are sugars, starch and fibre? 

Sugars, starch and fibre are the three categories of carbohydrates. Sugars and starch raise your blood glucose levels and fibre does not.


Sugars make food sweet. Sugars can be naturally occurring, such as in milk and fruit. Or sugars can be added by a food manufacturer, like in candy or cake. Honey, molasses, maple syrup and white or brown sugar are also examples of sugars. It’s wise to cut back on added sugar. It should make up no more than 10 percent of your total calories. In a 2000 calorie diet, 10 percent of calories from sugar is equal to 50 grams (or about 3 ½ tablespoons) of sugar per day. More than 10 percent of calories from sugar can increase blood glucose levels in some people. For more on sugar, read what you need to know about sugar.


Starches are the type of carbohydrate found in grains (rice, pasta, breads, crackers, cereal and so on), some vegetables (potatoes, yams, cassava, corn) and legumes (beans, lentils and dried peas).  Starches cause blood glucose levels to rise, but it doesn’t mean you shouldn’t eat them.  The right amount of carbohydrate for you depends on your size, medications and physical activity levels. You can use a tool like the glycemic index to figure out which carbohydrate-containing foods raise blood glucose more slowly.


Fibre does not raise your blood glucose. There are two types of fibre - insoluble and soluble. For people with diabetes, soluble fibre may help manage blood glucose. It can also help manage blood cholesterol levels. This is important since high cholesterol is a risk factor for developing diabetes. Soluble fibre is found in:

  • Barley
  • Fruits, like apples and pears
  • Legumes like beans, lentils and peas
  • Oats
  • Psyllium (found in some cereals)
  • Vegetables like eggplant and okra 

Insoluble fibre helps promote regularity and a healthy digestive system. Read more about fibre here. The Canadian Diabetes Association recommends that people with diabetes aim for 25-50 g of fibre per day. If you are not used to eating fibre, add high fibre foods slowly and drink lots of fluids. This will help prevent upset stomach, gas and bloating. Helpful hint: When reading food labels to find high fibre foods, look for 4g or more of fibre per serving!

The bottom line 

If you have diabetes, pay special attention to the type and amount of carbohydrate you eat. Foods can have different types of carbohydrates, such as sugar, starch and fibre. The right amount and type of carbohydrate for you depends on your size, medications and physical activity levels. It can be tricky, so work with a Registered Dietitian to figure out a meal plan that balances carbohydrate foods and keeps you healthy. 

You may also be interested in:

Getting to Know the Glycemic Index
The Benefits of Eating Fibre
Take the Diabetes Quiz

Last Update – May 10, 2018

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