Yogurt in grocery store The dairy aisle is crammed with all kinds of yogurt. Many claim they contain "probiotics," but do you know what those are?     "Not really."     "No clue. Do you have a clue?" "No"  John Santa, Consumer Reports Health   "Probiotics are beneficial bacteria that can ease digestive problems, and may lower your cholesterol and in some cases can strengthen your immune system."     Yogurt    Packing up yogurt  Yogurt   Is there a difference between yogurts that claim to contain "probiotics" and those that don't? To find out, Consumer Reports sent samples of strawberry yogurts to an outside lab. The tests included the leading brands Dannon, Yoplait, and Stonyfield.  Linda Greene Consumer Reports, "It turns out that all the yogurts we tested, whether they were labeled probiotic or not, had high levels of bacteria that were good for you."    However, there were differences when it came to nutrition and taste. The Greek yogurts Consumer Reports tested had more protein, and they were thicker and creamier. But with any yogurt, look at the label for total sugar content.           Linda Greene, "Several products we looked at contained about 25 grams of sugar per serving. That's equal to about six teaspoons of sugar!"    Consumer Reports also had its trained taste testers try the yogurts. All rated at least good, and two were excellent for taste.