By Claire Cronier
Are you worried about the calories in sweeteners like sugar and honey? Are sugar substitutes a better way to sweeten foods without the extra calories? Let’s consider the sweet choices available to people with diabetes, and how they fit as part of a healthy diet.
Two types of sweeteners
There are two basic categories of sweeteners, nutritive and nonnutritive. Nutritive sweeteners provide calories or energy to the diet at about four calories per gram, just like carbohydrate or protein. Common examples of nutritive sweeteners include white and brown table sugars and molasses, honey, and syrups such as maple and corn. These are all sweet tasting because of the presence of glucose and fructose, alone or together as sucrose. Sugar alcohols known as sugar relatives are another category of nutritive sweeteners. They are derived from fruits or produced commercially from dextrose. The most common include: sorbitol, mannitol, xylitol and maltitol. Sugar alcohols also provide energy to the body and may affect your blood glucose. Nonnutritive sweeteners, also called sugar substitutes or artificial sweeteners, do not provide calories and will not influence blood sugars. These include: saccharin, cyclamate, aspartame, sucralose and acesulfame potassium.
Saccharin is the oldest of the nonnutritive sweeteners, and is available under the brand name HermesetasTM . In Canada, saccharine is available only as a tabletop sweetener and is sold in tablet or powder form in pharmacies. It is 300 times sweeter than sucrose (table sugar) but has a slightly bitter/metallic aftertaste. Because saccharine is not metabolized in the human body, it does not contribute energy or calories. Saccharin has been the center of controversy for many years because of its alleged relationship with cancer; however, research studies have been unable to find direct associations.
Aspartame is marketed for commercial use under the brand name NutraSweetTM and is found in breakfast cereals, soft drinks, desserts and candy. It is also known as EqualTM, a powder for use in the home. Although technically considered a nutritive sweetener contributing four calories per gram, aspartame is 200 times sweeter than sugar and very little is needed to achieve sweetness. Therefore, its calorie contribution is negligible. Aspartame is made up of two amino acids, the building blocks of protein: aspartic acid and phenylalanine. It is therefore digested and metabolized the same way as any other protein foods. People diagnosed with phenylketonuria (PKU), a rare hereditary disease, need to limit phenylalanine intake and therefore should not sure aspartame.
Cyclamate is marketed under the brand name SucarylTM and is used in Sugar TwinTM and Weight WatchersTM. It is 30 times sweeter than table sugar and has no aftertaste. This sweetener is heat stable, so it can be used in hot and cold foods. Cyclamate is heat stable, so you can cook and bake with it without losing its sweet taste. In Canada, cyclamate can only be purchased as a tabletop sweetener or as a sweetening additive in medication.
Sucralose, available as a tabletop sweetener and as an ingredient in food processing, is marketed as SplendaTM. Sucralose is a white crystalline powder made from sugar itself. Sucralose is 400 to 800 times sweeter than table sugar. Because it is stable even when subjected to extreme heat or cold, sucralose can be used in a variety of cold and hot drinks, pastries and baked goods, and frozen and canned fruits and vegetables. Although its chemical structure is very close to that of sucrose or table sugar, sucralose is not recognized by the body as a carbohydrate and has no effect on insulin secretion or overall carbohydrate metabolism in healthy human beings.
Acesuflame Potassium (AceK) is the latest nonnutritive sweetener approved by Health Canada. It is marketed under the brand name SunettTM. AceK is found in beverages, fruit spreads, baked goods, dessert bases, tabletop sweeteners, hard candies, chewing gum and breath fresheners. It is 200 times sweeter than table sugar. People who are on a potassium restricted diet or have sulfa-antibiotic based allergies should discuss the use of Ace-K with their physician.
All sweeteners available in Canada go through rigorous testing. Once they have been approved it means that they are suitable for use by all Canadians, including those with diabetes.
Although non-nutritive sweeteners taste sweet and do not add calories to food, they often cannot be substituted directly for sugar in recipes. Sugars and syrups also add to the texture and colour of foods in ways that these sweeteners will not. Many of the manufacturers have developed special recipes for using these products.
Because sugar alcohols are absorbed and metabolized by the body more slowly, they were once believed to be good sugar substitutes for people with diabetes. However, sugar alcohols sometimes cause abdominal discomfort and, because they provide calories, they are not as popular a choice as artifical sweeteners. The real benefit of sugar alcohols is related to the inability of mouth bacteria to use them as a source of energy. Therefore, they do not contribute to dental caries (cavities). Some products that may contain sugar alcohols include hard candy, chocolate, table syrups, chewing gum, jams and jellies and some cough lozenges and syrups.
Are these sweeteners safe?
Health Canada considers all available scientific information on the effectiveness and safety of sweeteners. Regulations are then developed to identify how they should be used and what amounts should be allowed. A recommended daily intake (RDI) has been set by the Canadian government for most sweeteners. Since RDIs are based on body weight and may therefore be different for everyone, ask your dietitian about your own RDI if you use sweeteners regularly. Current evidence suggests that ‘normal use’ concentrations of artificial sweeteners are not a health risk.
The real thing
In the past, people with diabetes were told to avoid sugars and other carbohydrates. Current research shows that it is the amount of carbohydrate eaten and the rate of its digestion that are the most important factors in blood glucose control. Sugars can be included in a healthy diet as a part of a carefully planned meal plan. Carbohydrates, including sugars, should be spread evenly over the day, as part of slowly digested meals. If you have questions about sugars and your diet, check with your registered dietitian, a certified diabetes educator or the Canadian Diabetes Association.
Of course, sugars do provide some calories, but foods or drinks made with artificial sweeteners may not always be low in calories either. If you are concerned about calories, it is important to check the nutrition information panel on the food label. Remember, fat provides nine calories per gram, more than twice the amount provided by carbohydrate (including all sugars) and protein.
When used in moderation as part of a healthy and wellbalanced diet, sugar substitutes can contribute to the enjoyment of eating. They are not, however, a miracle solution in achieving or maintaining a healthy weight nor in managing diabetes. When trying to lose weight, your best bet is to follow the Canada’s Food Guide, and to be a little more active each day. Making sure that you are getting all the nutrients you need to maintain good health should be your first priority.
Claire Cronier MSc, RD is a nutrition consultant from Kingston, Ontario. She gratefully acknowledges the assistance of Marjan Shalchi MSc, RD in the writing of this article.