By Julie Redfern, R.D., L.D.N.
Artificial sweeteners, also known as non-nutritive sweeteners, are food additives that sweeten food without adding calories. They have no calories because the body doesn't absorb them, or absorbs them in very small quantities.
The U.S. Food and Drug Administration (FDA) has approved five artificial sweeteners.
The Acceptable Daily Intake (ADI) is the weight of sweetener per kilogram of body weight that a person can safely consume every day over a lifetime without risk. It is a conservative estimate and reflects 1/100 of the maximum level that produces no adverse effects. The Estimated Daily Intake is an estimate of the weight of sweetener consumed per kilogram of body weight per day based on food consumption surveys.
Saccharin is the oldest artificial sweetener. It was "generally recognized as safe" (GRAS) by the FDA until 1972, when the FDA removed it from the GRAS list. In 1977 the FDA required a warning label on saccharin products due to studies that showed high doses could cause cancer in rats. Further research showed that the effect on rats did not apply to humans. So in 2000 the National Toxicology Program of the National Institutes of Health (NIH) concluded that saccharin was no longer a potential carcinogen and the warning label was no longer necessary. Saccharin, however, can cross the placental barrier so it is not recommend for pregnant women.
The average consumption of artificial sweeteners is well below the ADI. For example, one packet of Equal contains 35 milligrams to 40 milligrams of aspartame, one 12-ounce diet soda contains 225 milligrams of aspartame, and one 8-ounce yogurt contains 80 milligrams of aspartame. A 150-pound adult would have to drink approximately 15 cans of diet soda sweetened with aspartame to exceed the ADI. Likewise, it would take five cans of Diet Coke sweetened with sucralose, 8.5 packets of saccharin and 25 cans of Diet Coke containing Acesulfame-K to reach the respective artificial-sweetener ADIs. Again, ADIs are based on a conservative estimate for a lifetime consumption rate, so occasionally exceeding the level should have no harmful effects. In addition, many products contain a mixture of artificial sweeteners, which reduces the amount of each one used.
In recent years, another sweetener called Stevia has sparked some attention. Stevia comes from a South American shrub and has a sweet taste. It can't be sold as a sweetener because the FDA considers it an unapproved food additive. Why? Because the FDA hasn't received adequate evidence that the substance is safe. So it is marketed as a "dietary supplement." Dietary supplements are considered safe until proven otherwise. Neither the FDA nor the Joint Expert Committee on Food Additives has approved Stevia for use in commercial products.
Artificial sweeteners can be used as part of a healthy diet to help maintain or lose weight for some people. They also may be a great sugar substitute for diabetic patients who need to limit their carbohydrate intake. Studies have shown that for certain overweight individuals, using artificial sweeteners helps them lose weight, which lowers their blood pressure. Artificial sweeteners and the products that contain them have their place in a healthy diet, but they are not the panacea for weight management, nor should they displace other proven healthy foods, such as whole grains, fruits and vegetables.
Some people may have an allergic reaction to artificial sweeteners. Other people dislike the aftertaste the sweeteners often have. For these people, artificial sweeteners should be avoided. Instead, water can be flavored with a small amount of a favorite fruit juice, or a few drops of lemon or lime juice. Some low-calorie products are naturally flavored. Finally, just because a beverage or food product contains artificial sweeteners does not mean it can be enjoyed in unlimited quantities. High consumption of any non-nutritive beverage, such as soda, iced teas, fruit or juice drinks, especially by children, may decrease the appetite for more nutritious foods and beverages.
Julie Redfern, R.D., L.D.N attended the University of Vermont and completed her dietetic internship at the University of Cincinnati Medical Center. She is Manager of the Nutrition Consult Services at Brigham and Women's Hospital, and is Senior dietitian with the OB/GYN services, counseling both teens and adults on a variety of perinatal issues.
Rebecca Lynch, M.S. received her Master's degree from the University of Vermont and is a 2008 Dietetic Intern at the Brigham and Women's Hospital.