Updated

Walgreen Co has been sued by a California woman who accused the largest U.S. drugstore chain of deceiving customers into believing its vitamin E dietary supplement contributes to cardiovascular health.

The complaint, filed on Friday in federal court in Chicago, challenges a label on Walgreen's Vitamin E 400 IU Dietary Supplement that says the product "naturally contributes to cardiovascular health by helping to protect LDL cholesterol from oxidation which may cause cellular damage."

Andrea Trujillo, the plaintiff, said the representation was false and misleading because clinical studies show that vitamin E does not work as the retailer advertised.

Trujillo claimed to have paid $12 each for several bottles of the supplement at a Walgreen's in her hometown of Bakersfield, California.

"Plaintiff used the product as directed, and consistent with the scientific evidence that the product is not effective, the product did not work," the complaint said.

The statement in question has not been evaluated by the U.S. Food and Drug Administration, according to the label, which was reproduced in the complaint.

Walgreen spokesman Jim Graham declined to comment.

A lawyer for Trujillo did not immediately respond to a request for comment.

According to the National Institutes of Health, vitamin E has an antioxidant function that protects cells from damage caused by so-called free radicals, which can contribute to the development of cardiovascular disease and cancer.