More Canadians than ever are adding artificial sweeteners to their diet. The average Canadian consumes about 16 teaspoons of added sugar every day. Are sugar substitutes safe to use. Nutrition expert Leslie Beck investigates.
Q: Can artificial sweeteners help people lose weight?
When it comes to losing weight, it's not that clear artificial sweeteners actually help. When you consider that a 355 ml can of pop contains roughly 10 teaspoons of sugar and 150 calories, switching to "diet" can make a difference to your calorie intake, especially if you drink it daily. Over the course of a year, swapping regular for diet will save almost 55,000 calories, an amount that translates into a 15 pound weight loss. Previous research has found that dieters who use an aspartame-based sweetener are more likely to keep their weight off compared to dieters who don't use artificial sweeteners. But recent study findings question the ability of artificial sweeteners to promote weight loss.
In a study published this summer, researchers from the University of Alberta found young animals that became used to diet foods tended to overeat during meals of regular-calorie food. The scientists suspect that diet foods disrupted the animals' ability to learn how various flavours correlate with calories. These findings may have implications for young children. It's possible that a regular fare of low calorie snacks and diet soft drinks can prevent kids from learning how to properly regulate their food intake.
A Purdue University study also suggests that artificial sweeteners might weaken the body's natural ability to regular calorie intake. Rats fed artificial sweeteners consumed three times more calories than rats given sugar.
Q: How safe are artificial sweeteners? Do they increase cancer risk?
Questions about artificial sweeteners and cancer arose when early studies showed cyclamate (the ingredient in Sucryl, Sugar Twin) combined with saccharin cause bladder cancer in lab rats. Neither saccharin nor cyclamates are permitted to be added to foods or beverages sold in Canada, but they are sold as table top sweeteners. (Based on pressure from food industry, Health Canada has reviewed recent studies on saccharin and concluded that research in rats is not applicable to humans. The government intends make regulatory changes to allow saccharin to be added to foods.)
Despite negative reports on the internet that aspartame (Nutrasweet, Equal) causes brain cancer, multiple sclerosis, seizures and Alzheimer's disease, there is no scientific evidence to support these claims. Aspartame did come under recent scrutiny, however, when Italian researchers found more lymphomas and leukemia in rats fed very high doses of the chemical (the equivalent to drinking 8 to 2,083 cans of diet pop per day). Health Canada reviewed the data and concluded existing regulations on use of aspartame did not need to change. In humans, aspartame has not been linked with increased cancer risk.
In 2006, the U.S. based National Cancer Institute published five-year data on 285,079 men and 188,905 women ages 50 to 71 years. Higher aspartame intakes (more than three cans of diet pop per day) were not associated with an increased risk of cancers of the brain or blood.
Q: What's the difference between all these sugar substitutes? What's safe and what's not?
Aspartame (Equal, Nutrasweet). Aspartame has been on the market for over twenty years - since 1981. It's added to foods and sold as a table top sweetener. It's made from two amino acids (phenylalanine and aspartic acid). Despite all the controversy, not one credible scientific study has linked aspartame to cancer or any other disease. That said, some people are sensitive to aspartame and report aspartame use has been reported to cause headaches and other reactions in sensitive people.
And because aspartame contains the amino acid phenylalanine, individuals with a metabolic disorder called PKU should avoid using it. PKU is an inherited disease in which the body cannot dispose of excess phenylalanine. It is safe during pregnancy. When heated, aspartame loses its sweet flavour; it's not suitable for cooking or baking.
Sucralose (Splenda). Sucralose has been approved for use in Canada since 1991. It's also found in many diet foods and also sold as a tabletop sweetener. Contrary to popular belief, sucralose is not natural because it is made from sugar.
Sucrose is made using a multi-step chemical process that adds chlorine to sugar molecules. Interestingly, Whole Foods Market does not carry products with sucralose (or aspartame) based on the fact it's an artificial chemical which lacks long term data from human studies. It's heat stable so it can be used for baking. It is considered safe during pregnancy.
Cyclamate (Sugar Twin, Sucryl).
These sweeteners are approved as a drug, but not as a food additive. You'll notice that on Sugar Twin's package, it carries a warning label that it should only be used under physician's advice. It is not considered safe during pregnancy.
Acesulfame potassium.
This sweetener is found in foods and drinks usually blended with another artificial sweetener. Some experts are wary about this sweetener because its safety is based on only a few animal studies conducted in the 1970's. It is considered safe in pregnancy. People on low potassium diets should avoid foods containing acesulfame potassium.
Q: How much artificial sweetener is safe to use?
Health Canada has established "Acceptable Daily Intakes" for sugar substitutes. This is the amount of artificial sweetener that, if consumed each day for the duration of a person's life, would be considered safe.
When it comes to aspartame, the ADI is 40 mg/kg/day - that's equivalent to about 20 cans of diet pop or 82 packets of Equal everyday for a 150-pound person. When it comes to sucralose, the ADI is 9 mg/kg body weight per day - 40 cups Ocean Spray White Light Cranberry Cocktail or 51 packets of Splenda for a 150 lb. person.
Q: Do you advise your clients to use artificial sweeteners?
Unless someone has diabetes, no. Although Health Canada approved sugar substitutes are considered generally safe, no one really knows the effect of consuming these chemicals for years and years. That's especially true for kids who are brought up on artificial sweeteners. And let's remember that real sugar is hardly toxic. Even people with diabetes can safely consume a little bit of sugar.
The key is moderation. Train your taste buds to prefer less sweet taste. Try skipping the teaspoon of sugar or packet of sweetener in coffee and on breakfast cereal. Drink sparkling water with a splash of fruit juice, instead of diet soft drinks. Eat smaller portions of sweets, rather than larger amounts of sugar-free substitutes.
