In the course of fermentation, small amounts of alcohol are also produced when sugar is broken down. The alcohol content depends on the composition of the culture, the temperature during fermentation and the ingredients. Basically, you can assume that the alcohol content of homemade kefir is between 0% and a maximum of 2%, about the same as in an alcohol-free beer. Did you know that ripe bananas, orange juice and even some types of white bread have similarly low amounts of alcohol?
People suffering from alcoholism and dry alcoholics are nevertheless recommended avoiding fermented drinks in large quantities.