Newswise — Increased awareness of the importance of digestive health has quickly turned into a multi-million dollar industry. According to Global Industry Analysts, the probiotics market is expected to exceed $29 billion by 2015 and expected to rise 7 percent a year over the next five years.

Within the digestive tract is a complex microscopic ecosystem known as the gut microbiome, which researchers and physicians say has a stronger impact on our well-being than ever imagined. The average consumer now knows how foods can keep good bacteria, or gut flora, in their daily diets. In response, food companies have rapidly expanded the food market. Kari Kooi, registered dietitian at Houston Methodist Hospital, explains how to navigate the digestive health food niche and find options that offer health benefits beyond basic nutrition.

• Separating health from hype when evaluating probiotic products: Probiotics are friendly bacteria that promote digestive health and can reduce bad bacteria. Foods that are cultured or fermented naturally contain probiotics, but now probiotics are being added to many processed foods. The benefits of probiotic cultures can be greatly weakened when they are removed from their original sources and added into processed foods such as energy bars or frozen yogurt. Extreme temperatures from baking and freezing can drastically alter the number of viable probiotics. So stick with yogurt for a sure thing.

• The dynamic duo: Prebiotics are food for probiotics. This relationship means that probiotics rely on a steady supply of food from prebiotics so that they can flourish. Keep your probiotic microflora happy and well-fed by filling up your grocery cart with fiber-rich plant foods. Top sources of prebiotics include bananas, garlic, onions, leeks, artichokes, asparagus, whole grains and legumes like lentils, beans and peas.

• Cultured dairy reigns supreme: Even in the midst of the fermented food revolution where kimchi, kombucha and sauerkraut are prized for their probiotic benefits, cultured dairy products such as yogurt remain the most potent probiotic source. Cultured dairy also has a short shelf life and offers a non-acidic environment, thereby keeping the probiotics alive and active. Yogurt is the most popular cultured dairy product, but store-bought and homemade kefir is becoming increasingly popular. While yogurt and kefir both contain probiotics, kefir has an extremely diverse population of strains in comparison.

• How to buy the best yogurt: Along with the increasing number of different yogurts on the market, comes fiercer competition between brands. Companies looking to capitalize in this market are introducing different styles of yogurt beyond Greek. Not all yogurts are nutritionally equal. To select superior yogurt with probiotic power, check for the “Live Active Cultures” seal. Yogurts that say “heat treated after culturing” on the label should be avoided because they were pasteurized after the live strains were added, which deactivates the probiotics. Also check the ‘best if used by’ date as probiotic potency decreases with age. Fage plain, non-fat or 2 percent Greek yogurt or Chobani yogurt are the best choices with twice as much protein and less sugar. Beware of added sugar in many fruit-flavored yogurts. Assess sugar content by checking the ingredients list and avoiding yogurts that have sugar listed as the first or second ingredient, as this indicates a sugar-packed product.

• What to know before purchasing a probiotic supplement: The journey probiotic supplements make from the lab to the gut is long and full of variables, making the survival of live and active cultures dependent upon how the strains are cultivated and handled. Probiotics are sensitive to oxygen, temperature and moisture, so it’s important to ensure the product has been quality assured by an outside lab. Always discuss probiotic supplement use with your physician since there may be risk to using them with some conditions such as a weakened immune system. The best and least expensive option for obtaining probiotic benefits is to enjoy foods that naturally contain live cultures.

• Should I take probiotics when I am taking antibiotics? Research has shown that taking probiotics during antibiotic therapy does reduce side effects such as diarrhea. Ramping up probiotic food sources such as yogurt can balance the effects of the drug. • An increasing number of doctors are recommending probiotics: Probiotics are being recommended for treatment of irritable bowel syndrome, certain skin conditions and urinary tract infections. Also, they are recommended to promote oral health and prevention of allergies.

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