Seeking Ferment

· Add chicory to your coffee . This practice was popular during World War II, when coffee supplies were limited. Chicory is gobbled up by bifidobacteria and seems to foster growth of this healthful strain in the colon.

· Eat a cup of yogurt daily. It's a fermented food that contains various strains of probiotics, depending on the product. So mix and match brands to get the most impact. For example, Stoneyfield yogurt contains six strains of probiotics. Activia, introduced to the United States by Dannon earlier this year, provides a proprietary strain of bifidobacteria that company studies suggest improves regularity. Research also suggests that foods containing probiotics must be eaten daily to keep healthy bacteria thriving in the colon.

· Sip buttermilk, kefir or drinkable yogurt. They're all fermented foods that contain healthy bacteria. Read labels to choose the brands with the least fat.

· Top your salads with a little blue cheese . Not only does it add flavor and bone-preserving calcium, but it also delivers healthy bacteria. Other cheeses that provide probiotics include Roquefort, Stilton and Shropshire.

· Have some tofu . This fermented soybean product is a plant-based source of healthy bacteria.

· Expect to see more functional foods with healthy bacteria. At the University of Reading in England, Robert Rastall, head of food and bioprocessing sciences, has teamed with the U.S. Department of Agriculture to see if agricultural waste such as citrus peels could be turned into probiotic food ingredients. Also emerging: synbiotics -- a mixture of healthy bacteria and the food needed to keep them vibrant as they move through the acid-filled stomach and the bile-salt-filled small intestine before reaching the colon.

· Stick to food sources of healthy bacteria. Rastall and his colleagues tested probiotic dietary supplements from around the world. They found that some products had sterile bacteria that could not colonize the intestines. Others "didn't contain the bacteria they were supposed to, and one or two brands had bacteria that were harmful," Rastall says. ·

Join the Lean Plate Club Web chat from 1 to 2 p.m. today at www.washingtonpost.com/leanplateclub, where you can also subscribe to the free Lean Plate Club e-mail newsletter.