If you have diabetes, you do not need to avoid sugar (carbohydrates) completely. In fact, understanding the role of the carbohydrates you eat in each meal is essential. You can help control the level of glucose in your blood by paying attention to the amount of carbohydrates you eat.
Carbohydrates, fats and proteins - the body’s main forms of nutrients - are called macronutrients. Carbohydrates have a very important job. All of the carbohydrates that you eat turn into glucose, which is carried in your blood to all the cells in your body. Glucose provides you with the energy you need for everything you do – to walk, think, blink and breathe. Your body needs carbohydrates to function just like a car needs gasoline to run. You need to know which foods contain carbohydrates, since all of these foods affect your blood glucose levels.
Many foods contain different types and sources of carbohydrates. Carbohydrates are found in cereals, breads, crackers, rice, pasta, other grain products, legumes, vegetables, fruit, dairy products and refined sugars. Sugar is only a small part of many of these foods.
Carbohydrates are made up of sugar molecules called saccharides. The way in which sugar molecules are joined together determines the different types of carbohydrate. They are generally classified into two categories - simple and complex carbohydrates.
Simple carbohydrates consist of either one sugar molecule (a monosaccharide) or two sugar molecules joined together (a disaccharide). Since simple carbohydrates are small molecules, they do not need much processing by your body. They quickly enter the bloodstream and raise blood glucose levels, providing a fast source of energy. Sugars come from fruit (fructose), some vegetables, milk products (lactose) and from “added sugar” (white and brown sugar, honey, syrup, molasses and candies). It is important to choose the healthier options of fruit and milk products because they contain essential nutrients. The ‘added sugars’ contain only ‘empty’ calories – high in calories but without much nutritional benefit. Foods like candy, cake and cookies do not contain important nutrients like vitamins, minerals and fibre. Eat less of these foods, and choose complex carbohydrates instead.
Starches are complex carbohydrates. Breads, cereals, pasta, rice, some vegetables and legumes consist of chains of saccharides attached together in different patterns.
These large chains must be processed by the body before they can be used for energy. Molecules are picked off the end of the chain as needed. Unlike simple carbohydrates, complex carbohydrates do not raise blood glucose levels quickly. Instead, they provide a steady release of glucose into the bloodstream. Many foods high in complex carbohydrates have another advantage since they also contain other important nutrients such as vitamins, minerals and fibre.
Dietary fibres are found in foods such as fruits, vegetables, legumes, and whole grain breads and cereals. Foods high in fibre tend to be absorbed more slowly into the blood stream – this will help you maintain good glucose control.
If you have diabetes, you have probably been told to keep track of the amount of carbohydrate you eat at each meal each day. The Canadian Diabetes Association 2003 - Clinical Practice Guidelines for the Prevention and Management of Diabetes in Canada recommends that 50 to 55 per cent of your daily calories should come from carbohydrates. As a general rule, 10 per cent of those carbohydrates can come from simple carbohydrates such as ‘added sugar’ and sweets without harming blood glucose control.
Eating one gram of carbohydrate provides 4 calories of energy (4 kilocalories) – less than half the calories found in one gram of fat (1 gram of fat = 9 calories). This means you can eat twice the amount of carbohydrates than fat and still take in the same amount of calories.
You may also choose foods that use ‘sweeteners’ rather than sugar. In Canada, the use of artificial sweeteners (such as aspartame, acesulfame potassium, cyclamates or sucralose) is acceptable. Foods sweetened with sugar alcohols (i.e. maltitol, mannitol, sorbital, isomalt and xylitol) are safe for use in limited amounts.
You can better manage your blood glucose levels by staying aware of the types and amounts of carbohydrates you eat. It is also important to distribute or divide your carbohydrates evenly into meals (and snacks if needed) throughout the day. Carbohydrate amounts vary from person to person. Talk to your dietitian or diabetes educator to help you work out the amount of carbohydrates that is right for you.
It is important to remember that your blood glucose levels are affected by the total amount of carbohydrates from all carbohydrate-containing foods that you eat. You can eat food that has sugar in it – just do so in moderation. Foods high in processed or refined simple sugars provide calories but have few nutritional benefits. Although you may want to limit these, you do not have to cut them out altogether. Choose complex carbohydrates more often as they also provide vitamins, minerals and fibre.
The key to successful healthy eating is moderation and taking one day at a time. Canada’s Food Guide to Healthy Eating is the standard for all Canadians, with or without diabetes. The food guide emphasizes eating a variety of healthy foods, focusing on vegetables, fruit, whole grain products and low-fat milk and milk products and leaner meats. If you have diabetes, it is important to stay as healthy as you can by: