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The problem with the stated carbohydrate content on the packages of fermented food products arises because the government makes manufacturers count the carbohydrates of food "by difference." That means they measure everything else including water and ash and fats and proteins. Then "by difference," they assume everything else is carbohydrate. This works quite well for most foods including milk. However, to make yogurt, buttermilk and kefir, the milk is inoculated with the lactic acid bacteria. These bacteria use up almost all the milk sugar called "lactose" and convert it into lactic acid. It is this lactic acid which curds the milk and gives the taste to the product. Since these bacteria have "eaten" most of the milk sugar by the time you buy it (or make it yourself.) At the time you eat it, how can there be much carbohydrate left? It is the lactic acid which is counted as carbohydrate. Therefore, you can eat up to a half cup of plain yogurt, buttermilk, or kefir and only count 2 grams of carbohydrates (Dr. Goldberg has measured this in his own laboratory.) One cup will contain about 4 grams of carbohydrates.