The question: What's the difference between yogurt and kefir?
The answer: Yogurt and kefir are both cultured milk products rich in protein, calcium, B vitamins and potassium. Both have a similar tart, slightly sour taste and can be purchased plain or flavoured with fruit or vanilla. They also improve lactose digestion, since the live cultures used to make them break down milk sugar. Their differences lie in consistency and the numbers and types of beneficial bacteria they contain.
Kefir has a thinner consistency than yogurt and is typically sold as a beverage. You can drink it, pour it over cereal and granola, or blend it with fruit to make a smoothie. In fact, kefir can be substituted for yogurt in many dishes. Most kefir products are slightly effervescent, although some companies make a "flat" kefir drink.
Both yogurt and kefir are a source of probiotics, live organisms (like bacteria and yeast) that, when consumed in certain amounts, exert health benefits. Probiotics are normally found in your digestive tract as part of the intestinal flora, a community of more than 400 species of bacteria. Here, they help inhibit the growth of unfriendly, disease-causing bacteria and stimulate the body's immune response.
Kefir, however, typically contains three times the amount of probiotic cultures than yogurt. To make kefir, milk is fermented with a mixture of 10 to 20 different types of probiotic bacteria and yeasts; most yogurts are made using only a few. Liberté organic kefir, for instance, delivers 40 billion probiotic organisms per half cup, while most probiotic yogurts contain roughly one billion per serving.
A higher probiotic count per serving means bigger potential benefits to your digestive health and immune system. Growing evidence suggests that some probiotics can help prevent allergies and eczema; alleviate bloating and constipation; treat inflammatory bowel disease; lower elevated cholesterol and blood pressure; and possibly guard against colon cancer.
If you're stuck on yogurt, give kefir a try. You'll get more probiotic power, but whether a daily drink of kefir does more than promote digestive health remains to be seen. There are simply too few well-controlled studies conducted in people. (Ditto for yogurt.)
Whether you eat yogurt or kefir – or both – choose a product that's low in added sugars. Ideally, opt for plain versions and add your own fruit for flavour.
Leslie Beck, a registered dietitian, is the national director of nutrition at BodyScience Medical. She can be seen every Thursday at noon on CTV News Channel'sDirect (www.lesliebeck.com).
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