Dear Mr. Wizard:

One recent afternoon, over a few of our favorite beverages, a friend and I got into a good-natured argument. My friend is a diabetic (and a beer lover) so calorie and nutrition information is very important to him. We were debating just where the calories in beer come from. My friend’s opinion is that the alcohol provides the calories, based on the fact that a beer and a shot of liquor are considered equivalent. Having recently read the article on creating low calorie beers using "Beano," (April, 2001) I hypothesized that the majority of the calories in beer must come from unfermented carbohydrates. Please educate us.

Walter Scott
Reisterstown, Maryland

Mr. Wizard replies:

There is really no reason to argue about this because you are both partially correct. An average 12-ounce serving of a "domestic-style" beer contains about 14 grams of ethanol and 11 grams of carbohydrate. In caloric terms this equates to 98 kcals from ethanol and 44 kcals from the carbohydrate, for a total of 142 kcals. The most effective methods of making lower calorie beer involve reducing the alcohol content, residual carbohydrate or, most commonly, a combination of both. The article on using Beano to make a light beer focused on reducing the residual carbohydrates by increasing wort fermentability.