The Food and Drug Administration said in a warning letter to General Mills that language on the Cheerios box suggests the cereal is designed to prevent or treat heart disease by lowering cholesterol. Regulators say that only FDA-approved drugs are allowed to make such claims.
Among other claims, the labeling states: "you can lower your cholesterol 4 percent in six weeks."
The FDA allows companies that market whole grain foods like Cheerios to highlight their ability to reduce the risk of heart disease. While the box carries that claim in the lower left hand corner, the language about cholesterol is much larger and appears separately - something the FDA does not allow.
Regulators also object to the company's claim that Cheerios can lower cholesterol by 4 percent, since companies are not allowed to quantify the benefit of their foods.
Additionally, companies that make claims about their whole grain foods are supposed to mention that fruits and vegetables are also part of a fiber-rich diet. General Mills' labeling does not include that information.
"Therefore, your claim does not convey that all these factors together reduce the risk of heart disease and does not enable the public to understand the significance of the claim in the context of total daily diet," states the FDA.
The warning letter, dated May 5, was posted to FDA's Web site Tuesday.
General Mills said the health claims on Cheerios have been approved for 12 years and the FDA's complaints deal with how the language appears on the box, not the cereal itself.
"The science is not in question," said spokesman Tom Forsythe in a statement. "The clinical study supporting Cheerios' cholesterol-lowering benefit is very strong."
Cheerios is the best-selling cereal brand in the U.S., with sales of $1.4 billion last year, according to General Mills.
The Minneapolis-based company said it would work with the FDA to address FDA's complaints. The warning letter asks the company to correct the problems within 15 business days of receipt.
The FDA regularly issues warning letters to companies that do not follow regulations for manufacturing and marketing. The letters are not legally binding, but the agency can take companies to court if they are ignored.
In recent years the FDA has begun cracking down on manufacturers who overstate the benefits of their products, amid increased demand for healthy foods.
Shares of General Mills Inc. rose 40 cents to $53.31 in morning trading.