Kefir by Ray Sahelian, M.D.

Kefir is a fermented milk beverage. Kefir is an ancient drink from the Caucasus Mountains that looks like liquid yogurt. Traditional kefir is tart - even sour - and contains a bit of carbonation and some alcohol from the fermentation. However, much of the kefir sold commercially in the United States is neither carbonated nor alcoholic. I personally enjoy drinking kefir, especially the ones that have raspberry or strawberry. The problem with kefir is that it is so tasty, one can easily keep drinking a glass of kefir several times a day.

How is Kefir made?
Kefir is made by adding a live culture - called kefir "grains" - from a previous batch of kefir to room-temperature milk (usually from a cow, goat or sheep. The cultures are a combination of bacteria and yeasts, usually lactobacillus acidophilus and Saccharomyces kefir.
   The milk fermentation is achieved by the of kefir grains, a cluster of microorganisms held together by a polysaccharide matrix named kefiran. Kefir grains are an example of symbiosis between yeast and bacteria. They have been used over years to produce kefir, a fermented beverage that is consumed all over the world, although its origin is Caucasian. A vast variety of different species of organisms forming the kefir grains, comprising yeast and bacteria, have been isolated and identified. Kefir is a probiotic food. Probiotics have shown to be beneficial to health, being presently of great interest to the food industry. Kefir has been accredited with antibacterial, antifungal and antitumoural activities among other beneficial attributes.

Benefit of Kefir

kefir is a probiotic, which means it contains "friendly" bacteria. Kefir also contains calcium and protein. The viable lactic acid bacteria in fermented milk products, such as yoghurt and kefir, have been associated with increased lactose tolerance, a well-balanced intestinal microflora, antimicrobial activity, stimulation of the immune system and antitumoural, anticholesterolaemic and antioxidative properties in human subjects. A small amount of kefir a day or a few times a week is fine, but I don't think ingesting a great deal of milk products on a daily basis is very healthy.