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We Canadians like our sugar. Most of us consume the equivalent of 16 teaspoons a day from soft drinks, candy, frozen desserts, snacks, sugary cereals - the list goes on.

While there is no evidence that sugar causes diabetes, heart disease, cancer or hyperactivity, too much can be a problem if you’re trying to lose weight or control your blood-sugar level.

That's why many people are turning to artificial sweeteners - or sugar substitutes - as a means of cutting calories while satisfying their sweet tooth. The growing number of "diet" and "no sugar added" foods means you don't have to give up ice cream, cookies, soft drinks or even pancake syrup to cut sugar.

But not all artificial sweeteners are alike. While most are deemed safe when consumed in reasonable amounts, some remain dogged by safety concerns.

And when it comes to losing weight, it's not clear that artificial sweeteners help.

When you consider that a 355-millilitre can of pop contains roughly 10 teaspoons of sugar and 150 calories, switching to "diet" can make a difference to your calorie intake. Over the course of a year, swapping regular for diet will save almost 55,000 calories, an amount that theoretically translates into a 15-pound (6.8-kilogram) weight loss.

Previous research found that dieters who use an aspartame-based sweetener are more likely to keep the pounds off compared with those who don't use artificial sweeteners. But recent 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. In other words, if you learn to associate sweet tastes with few calories, even a high-calorie dessert may fail to fill you up.

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 regulate their food intake.

A study from Purdue University in Indiana also suggests that artificial sweeteners may weaken the body's natural ability to regulate calorie intake. Rats fed artificial sweeteners consumed three times more calories than those given sugar.

What about safety? Questions about artificial sweeteners and cancer arose when early studies showed cyclamate (the ingredient in Sucaryl, Sugar Twin) combined with saccharin cause bladder cancer in lab rats. Neither saccharin nor cyclamate are permitted in foods or beverages sold in Canada, but they are sold as tabletop sweeteners.

(Under pressure from the food industry, Health Canada has reviewed recent studies on saccharin and concluded that research in rats is not applicable to humans. The government intends to make regulatory changes to allow saccharin to be added to foods.)

Despite 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 recently come under scrutiny, however, when Italian researchers found more lymphoma and leukemia in rats fed very high doses of the chemical. 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. Last year, the U.S.-based National Cancer Institute published data on 285,079 men and 188,905 women aged 50 to 71 years. Higher aspartame intakes (more than three cans of diet pop a day) were not associated with an increased risk of cancer of the brain or blood.

Sucralose (Splenda) is often deemed more natural than other sugar substitutes because it's "made from sugar." While that's technically true, it's misleading. Sucralose is made using a multi-step chemical process that adds chlorine to sugar molecules.

Whole Foods Market does not carry products with sucralose (as well as aspartame and acesulfame potassium) based on the fact it's an artificial chemical that lacks long-term data from human studies.

The safety of some of today's most widely consumed artificial sweeteners is based on studies conducted decades ago.

In the case of acesulfame potassium (which is combined with other artificial sweeteners in foods), its apparent safety is based on only a few animal studies.

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.

Artificial sweeteners can be useful, particularly for people managing blood-sugar levels. But 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 a less sweet taste. Skip 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 small portions of sweets, rather than larger amounts of sugar-free foods.

Leslie Beck is a dietitian.