From cereals that boost immunity to yogurts that regulate digestion and juices that keep heart disease at bay, grocery stores in the U.S. are brimming with packaged foods and beverages that claim to improve health. Such declarations are good for business: sales of “functional foods”—those that manufacturers have modified to provide supposed health benefits—generated $31 billion in the U.S. in 2008, a 14 percent increase over 2006, according to Rockville, Md.–based market research firm Packaged Facts. But consumers are getting a rotten deal. Although health claims for foods may appear to be authoritative, in many cases science does not support them and the government does not endorse them. Not only do these products, many of which are nutritionally bereft, fail to deliver on their promises, but they may also give consumers a false sense of security that discourages them from taking more effective measures to attain wellness, such as exercise or medication.

In March the U.S. Food and Drug Administration issued warning letters to 17 food and beverage manufacturers concerning false or misleading health and nutrition claims on their products. It was an unusually expansive crackdown for the agency, whose regulatory power over food companies has declined over the past decades, thanks to Congress and the courts, which have tended to come down on the side of the food companies. The FDA’s move, accompanied by an open letter from Commissioner Margaret Hamburg about the importance of accurate nutrition labeling, was a significant step toward halting the exploitation of science by food marketers, but it does not go far enough in protecting consumers from deceptive marketing.

The FDA currently issues guide­lines for what claims companies can make about their foods. It allows statements about how products affect the normal structure and function of the body but prohibits unauthorized claims about disease. The agency, though, does not review compliance before food is packaged and shipped. Food products arrive at the stores emblazoned with questionable claims. Cheerios can lower cholesterol 4 percent in six weeks, asserted the box label, until the FDA sent General Mills a cease-and-desist letter in May 2009. Redco Foods’s Salada Naturally Decaffeinated Green Tea promised to tackle Alzheimer’s, rheumatism and cancer, until the March crackdown. The agency is then forced to play catch-up. Meanwhile the snake oil sits on supermarket shelves.

Holding health claims for food to the same scientific standards as those for drugs—and requiring manufacturers to convince the FDA of alleged benefits before releasing products for sale—would result in far fewer health claims on packaged foods, if recent developments in Europe are any indication. In 2006 Europe began holding food makers to rigorous scientific standards. Since then, the European Food Safety Authority has rejected, on the basis of insufficient evidence, a whopping 80 percent of the more than 900 claims they have assessed thus far. Among the rejects were claims about probiotic ingredients, which are commonly found in yogurt products and often touted for their alleged digestive benefits, and omega-3 fatty acids, which are frequently added to products ranging from orange juice to baby food and are often said to promote brain development. The simple act of asking for evidence is sometimes enough to reveal the shoddiness of a claim—some European firms drew supporting materials from Wikipedia, the American Heritage dictionary and the Bible.

Differences between the lenient U.S. system and the more restrictive European system are easily apparent. For instance, visitors to the Web site for Activia (—a yogurt product from Dannon—will have a very different experience depending on which country they indicate they are from. The U.S. version prominently displays the product’s putative health benefits, asserting that it can “help regulate your digestive system by helping reduce long intestinal transit time.” (It does not say explicitly that the yogurt helps to alleviate constipation, which would be a clear violation of the FDA prohibition of unauthorized claims about specific medical conditions.) The U.K. version, on the other hand, says only that the yogurt contains an exclusive bacterial culture and, like other yogurts, is a source of calcium and vitamin B12.

Industry representatives complain that having to prove claims about the health benefits of food would cost too much and take too long. It’s a lame argument. The nation is currently engaged in a struggle against skyrocketing rates of obesity and other diet-related diseases that are among the leading causes of death in the U.S. In this context, unsubstantiated health claims on processed foods are a harmful abuse of science that we should not tolerate.