Five Controversial Food Additives

The majority of food additives are safe. But manufacturers still add some ingredients best avoided--often to food products that aren't especially good for you anyway (think soft drinks or hot dogs). "Choose foods in the form closest to nature," advises dietician Joanne Larsen. Those will typically contain more vitamins and minerals. In other words, opt for fresh foods rather than those that have been processed with additives for a longer shelf life or to fill other needs of modern food production.

The Center for Science in the Public Interest, a nonprofit educational and advocacy organization that focuses on food safety, offers a chart on the merits and demerits of most food additives, both natural and manufactured. Here are five of the most controversial additives from CSPI's list. All have been approved by the Food and Drug Administration, but some health experts suggest that we cut back or eliminate them from our diet whenever possible.

Sodium nitrite. Bacon, sausage, hot dogs and smoked foods typically contain this preservative, which combines with amines in the stomach to form nitrosamines, a carcinogen also found in tobacco smoke. Although there's no proof that nitrite in food causes cancer, there's evidence linking it to the disease. One good reason not make those ballpark hot dogs a habit: in a 20-year study reported in 2006, researchers at the Karolinska Institute in Stockholm concluded that out of 61,433 Swedish women, those who ate the most cured meat doubled their chances of getting stomach cancer. Meat isn't the only place you'll get nitrates, though. Researchers in Barcelona recently reported a link between stomach cancer and fish, vegetables and smoked foods preserved with sodium nitrite.

Potassium bromate. Used to process flour, bromate has been the subject of much scrutiny and concern. A study by the FDA concluded that "it is reasonable, based on an extensive database, to assume that bromate induces tumors via oxidative damage." A committee of experts from the U.N. Food and Agriculture Organization and the World Health Organization deemed its use as a flour agent "unacceptable" based on evidence that it causes cancer in animals. It also appears to cause abnormalities in human blood cells in lab experiments. While potassium bromate has not been banned in the U.S., the FDA discourages bakers from using it--and at least one state, California, has approved a warning-label requirement that has led many bread makers to abandon the additive. Still, it's a good idea to check labels yourself if you want to avoid the additive.

Acesulfame potassium (or acesulfame-K). You're most likely to see this sugar substitute in products advertised as sweetened by Splenda, or sucralose, which manufacturers sometimes blend with acesulfame-K in baked goods, gelatin desserts, ice cream, iced tea and soft drinks. As Splenda became the top artificial sweetener, overtaking Nutrasweet (or aspartame), acesulfame-K became much more common in supermarkets.

Laura Tarantino, director of the FDA's Office of Food Additive Safety, says that "more than 90 studies support the use of acesulfame." The Center for Science in the Public Interest, however, argues that the FDA should reconsider the evidence, citing animal studies linking it to cancer. Chang Lee, chairman of the department of food science at Cornell agrees that the "controversy over the safety of acesulfame-K has not been completely resolved." In the meantime, if you've got concerns, there's an easy solution: satisfy your sweet tooth with fresh fruit--or real sugar.

Partially hydrogenated vegetable oil. You've heard plenty about potentially artery-clogging "trans fats" in the news; on food labels, they're found in "partially hydrogenated" (or just "hydrogenated") vegetable oil and are still used in crackers, baked goods and such restaurant foods as french fries or fried chicken. The case against trans fats is so strong that health departments in New York City and Philadelphia have limited their use in restaurant cooking; and several big food companies--including Starbucks, McDonald's and Frito-Lay--are cutting back on trans fats or eliminating them. Anyone with a family history of heart disease should take note and do the same.

Artificial food colors: Check the labels on favorite foods for FD&C Yellow No. 5 and No. 6 and FD&C Red No. 40, three synthetic colorings used in food that were cited in a study published last fall by the British medical journal The Lancet. Researchers followed 144 8- and 9-year-olds over six weeks--some of whom drank a juice containing a mix of the food colorings, others who drank uncolored juice (the food colorings had otherwise been eliminated from all the kids' diets). The result: the children who consumed the food colorings were significantly more impulsive and fidgety and also less attentive over the six weeks, although the study did not identify specific links between consumption and the agitated behavior. The researchers obtained similar results with 3-year-olds. An FDA spokesman says that "further testing on this issue is needed," but that the agency "has no reason to change our conclusions that the ingredients that were tested in this study that currently are permitted for food use in the U.S. are safe for the general population." Click here for more of the FDA's take on the safety of color additives.