Over the past 20 years or so, Americans have developed quite the sweet tooth, with an annual consumption of sugar at about 100 pounds per person. During these same years, many more Americans — particularly children — have become overweight and obese. Added caloric sweeteners may be one of the major reasons.
Sucrose and fructose
Sucrose, or table sugar, has been the most common food sweetener. In the late 1960s, a new method was introduced that converts glucose in corn syrup to fructose. High-fructose corn syrup is as sweet as sucrose, but less expensive, so soft-drink manufacturers switched over to using it in the mid-1980s. Now it has surpassed sucrose as the main added sweetener in the American diet.
Fructose once seemed like one of nutrition's good guys - it has a very low glycemic index. The glycemic index is a way of measuring how much of an effect a food or drink has on blood sugar levels; low glycemic index foods are generally better for you.
But fructose, at least in large quantities, may have some serious drawbacks. Fructose is metabolized almost exclusively in the liver. It's more likely to result in the creation of fats which increase the risk for heart disease. Moreover, recent work has shown that fructose may have an influence on the appetite hormones. High levels of fructose may blunt sensations of fullness and could lead to overeating.
Fruit-juice concentrates: Just empty calories
Fruit juices such as apple or white grape juice in concentrated form are widely used sweeteners. They're used to replace fats in low-fat products because they retain water and provide bulk, which improve the appearance and "mouth feel" of the food.
Although they may seem healthier and more natural than high-fructose corn syrup, fruit-juice concentrates also have high levels of fructose. Fruit-juice concentrates are another way that empty calories get into our diets.
In sweetening power, the sugar alcohols are closer to sucrose and fructose than to the super-sweet artificial sweeteners. They don't affect blood-sugar levels as much as sucrose, a real advantage for people with diabetes, and they don't contribute to tooth decay. Sugar alcohols are used in candies, baked goods, ice creams, and fruit spreads. Read the ingredients carefully, and you'll spot them in toothpaste, mouthwash, breath mints, cough syrup, and throat lozenges.
Sweeteners added to sports and juice drinks are particularly troubling because many people think those drinks are relatively healthful.
Researchers are beginning to document the adverse health outcomes. Harvard researchers reported that women who drank one or more sugar-sweetened soft drinks per day were 83% more likely to develop type 2 diabetes than women who drank less than one a month. Not surprisingly, they were also more likely to gain weight.
When children regularly consume beverages that are sweetened they're getting used to a level of sweetness that could affect their habits for a lifetime. A 2004 editorial in the Journal of the American Medical Association said that reducing the consumption of sugar-sweetened beverages "may be the best single opportunity to curb the obesity epidemic."
Artificial sweeteners sing a siren song of calorie-free and, therefore, guilt-free sweetness. The FDA-approved ones include acesulfame K (Sunett), aspartame (NutraSweet, Equal), neotame, saccharin (Sweet 'N Low, others), and sucralose (Splenda). All are intensely sweet.
There's a cyberspace cottage industry dedicated to condemning the artificial sweeteners, especially aspartame. Some fears are based on animal experiments using doses many times greater than any person would consume. But even some mainstream experts remain wary of artificial sweeteners, partly because of the lack of long-term studies in humans.
Even if safety weren't an issue, artificial sweeteners might still be a problem because they may set people (especially children) up for bad eating habits by encouraging a craving for sweetness that makes eating a balanced diet difficult.
Tips for cutting down your sweetener consumption
December 2006 Update