Kraft boasts that people have eaten 450 billion Oreo cookies since they introduced the chocolate wafer sandwich cookies with a creamy filling in 1912.

But if British-born attorney Stephen Joseph has his way, that culinary love affair will come to an end, at least until Kraft stops using hydrogenated or partially hydrogenated oils to make the cookies.

Kraft calls the suit filed in Marin County Superior Court just north of San Francisco baseless but Joseph says he is taking advantage of a provision of the California civil code that holds manufacturers liable for common products if not "known to be unsafe by the ordinary consumer."

The ingredient is used in thousands and thousands of products. In an interview on Monday, Joseph said, "I am probably full of hydrogenated fat because until two years ago I didn't know about it. I resent the fact that I have been eating that stuff all my life."

Hydrogenation adds hydrogen gas to vegetable oil, helping to solidify it into products such as margarine. Health experts say the process makes them as unhealthy as real butter, if not more so, as the hydrogenated fats act like cholesterol in the body. Trans fats are common in cookies and crackers and part of both the cookie and filling in Oreos. &nbsp &nbsp &nbsp &nbsp

'SHOCKING' CASE

"That's what's so shocking; that it has been so well hidden," said Joseph, who has set up an advocacy group called BanTransFats.com Inc. "I hope if nothing else comes of this lawsuit that more people know about trans fat than before."

Kraft says it is already testing alternatives to trans fats but said they will vigorously fight the lawsuit.

Its parent company Altria Group Inc. is also the owner of cigarette maker Philip Morris USA, itself no stranger to legal battles over product safety.

"We know the importance of good nutrition and we are committed to helping people lead a healthy lifestyle, but we have no choice than to draw the line against baseless lawsuits like this," Michael Mudd, Kraft's senior vice president for corporate affairs, said in an interview.

"We've been ... exploring ways to reduce trans fat in Oreos and those efforts are continuing," he continued. "You can make a cookie without trans fat but what you're trading off is the unique taste and texture that people have come to expect."

U.S. companies, the world masters in processed foods, are showing an awareness of trans fats. Frito-Lay, part of PepsiCo Inc., announced last year it would eliminate trans fats from snacks such as Doritos. McDonald's Corp. also said it would make French fries with less trans fat.

In February, a federal court threw out a lawsuit against McDonald's that claimed its burgers and fries cause obesity.