Fake Sugars and Fats: Net Benefits or Real Risks?
Susan M. Kleiner, PhD, RD
THE PHYSICIAN AND SPORTSMEDICINE - VOL 25 - NO. 4 - APRIL 97
Have you ever wondered whether that packet of sugar substitute you put in your tea is really safe to use? Or whether potato chips made with fake fat will help you cut back on fat and calories? These questions are not only on the minds of many consumers, but also are among the most important concerns of nutrition scientists and federal food regulators today.
Do Fakes Really Help?
People use sugar substitutes and fat replacers for three reasons: to help control their weight; to limit the symptoms or risk of conditions like diabetes, cardiovascular disease, and cancer; and to prevent tooth decay. Whether these products actually accomplish these goals is debatable.
Artificial sweeteners are a boon for people who have diabetes, but current research does not show that they help people reduce calorie intake or prevent obesity. In fact, saccharin may even stimulate the appetite. When used in combination with a total weight management strategy, artificial sweeteners may help to limit calorie intake (1), but casual use often leads to overeating as a reward for calories saved by using sugar-free foods (2). Studies do indicate, however, that artificial sweeteners help prevent tooth decay (3).
As with artificial sweeteners, when people substitute fat-replaced, low-calorie foods for high-calorie, high-fat foods, they often overcompensate for the calorie savings. However, short-term studies indicate that people who use this strategy do tend to consume less fat, reducing the negative effect of fat on blood cholesterol and lowering cancer risk (2).
There are several artificial sweeteners to choose from (table 1: not shown). The oldest artificial sweetener on the market is saccharin, developed in 1900. Cyclamate was introduced in the 1950s, but by the 1970s, claims that it increased the risk of cancer in animals caused the Food and Drug Administration (FDA) to ban its use in foods. Then in 1977, because of research suggesting that saccharin caused bladder tumors in rats, the FDA required a warning label on all saccharin-containing foods.
The FDA approved the use of aspartame in 1981, but no sooner was it approved than its apparent safety came into question. It was already well known that aspartame could be dangerous for people who had phenylketonuria (PKU), an inability to process phenylalanine, a component of aspartame. Products containing aspartame must carry a warning for individuals who have PKU. Depressed patients may also be adversely affected—one study had to be halted because of severe mood disruptions in patients who had a history of depression (4).
Questions about the risks of aspartame use by normal, healthy people are now also being raised. Whether the substance causes brain tumors in rats was a prominent FDA concern prior to its approval. Some researchers are claiming that there were flaws in the original FDA research and review process that showed the safety of aspartame.
The FDA stands by its decision to approve aspartame. However, John W. Olney, MD, who has been studying aspartame's effects on the brain for more than 20 years, disagrees with the decision. "Since about 5 years after aspartame was approved, there has been a striking increase in the incidence of malignant brain tumors," Olney, a neuroscientist and professor of psychiatry at Washington University in St Louis, told a television news reporter recently (5). He is not calling for a ban on aspartame. "I'm not saying that aspartame has been a proven cause of brain tumors," he said. "I'm saying that there is enough basis to suspect aspartame; that it needs to be reassessed."
Artificial fats (table 1) may or may not provide nutritional value. Some contain usable fiber, fat, or protein. The one product that contains no usable nutrients and has been approved for use in the United States is Olestra—marketed by Procter & Gamble, Cincinnati, as Olean.
Controversy surrounding fat substitutes has been focused on Olestra. Because your body cannot digest it, Olestra is virtually calorie free. Some people may experience a mild to severe laxative effect from its use. Reports that Olestra may also block the absorption of fat-soluble vitamins and carotenes (vitamin A-like substances) caused the FDA to require that all Olestra products be fortified with vitamins A, D, E, and K. The FDA approved Olestra in 1995, and a reevaluation of its effects on large numbers of people will be conducted in 1998.
Wise Use of Stand-Ins
The bottom line is that, to lose weight, you must create a calorie deficit by reducing calorie intake and increasing energy output. Fake sugars and fats might help you cut back on calories or fat, but you can't trick your body into a calorie deficit simply by using foods that contain them. Also, because the safety of some of these products is still in question, if you choose to use them in your diet, do so in moderation.
Remember, this information is not intended as a substitute for appropriate medical treatment. If you have nutrition concerns, consult a dietitian or physician.
Dr Kleiner is a private nutrition consultant to athletes in the Seattle area. She is a member of the American College of Sports Medicine; a member of the American Dietetic Association and its practice group, Sports and Cardiovascular Nutritionists (SCAN); and a fellow of the American College of Nutrition.
Copyright (C) 1997. The McGraw-Hill Companies. All Rights Reserved