So, does yogurt really boost your health?

One of the hottest food marketing trends these days involves adding live bacteria to dairy products as a way to boost health.

Now lawyers have filed a class-action lawsuit against yogurt maker Dannon, one of the biggest sellers of "probiotic" yogurts, saying the claims of a health benefit dupe consumers. The company's Activia and DanActive line of yogurt products contain live bacteria and claim to help regulate digestion and boost the immune system. The suit, filed in United States District Court in California, seeks redress for consumers who purchased the yogurt products based on what it says are "bogus claims."

From the Dannon website "Specialists at Dannon selected Bifidus Regularis for Activia because it survives passage through the digestive tract, arriving in the colon as a living culture. Once there, it plays a beneficial role in your intestinal ecosystem"

Gregor Reid, a scientist who runs the nonprofit Canadian Research and Development Center for Probiotics, said there's a "huge amount" of research done on the strains cited by Dannon - and their benefits are clear.

For the suit to contend Dannon's claims are unfounded, Reid said, is like saying "the New England Patriots aren't in the Super Bowl."