The Glycemic Index of Beer - Whats the Real Deal?
Beer has so little carbohydrate that it's difficult to test its GI. That's why we listed its GI and GL as 0 in earlier editions of the New Glucose Revolution series books. But eventually we decided that the valid way to test beer would be by comparing responses to a 10 g carbohydrate portion of beer (about 300 mL) with a 10 g carbohydrate portion of glucose (in GI testing a 50 g carbohydrate portion is normally used). In this test the GI came out as 66. The GL will be therefore be 66 x 10/100 = 6.6 (round up to 7).
Q: ‘I have diabetes, but I enjoy an occasional drink. Does the way a beer is brewed (ales, lagers, pilseners, stout etc.) have a significant impact on the final product and its sugar content?’
A: Generally, alcoholic beverages contain very little carbohydrate. Most wines and spirits contain virtually none; regular beer contains around 10 g carbohydrate per 12 fl oz can; stout around 14 g carbohydrate per 12 fl oz can while a light beer has from 3–7 grams of carbohydrate per serving (12 fl oz can). Compare this with 36 g carbohydrate in a can of regular (not diet) soft drink! So yes, a beer will raise your glucose levels but not excessively. And if you drink beer in large volumes (not a good idea really) then you could expect it to have a significant effect on blood glucose. Although we haven’t GI tested many brands of beer, there are some useful websites out there that will tell you how much carbohydrate there is in various brands. We use www.calorieking.com as a quick reference.
As for enjoying an occasional drink, researchers (Kaniz Fatima and Chris Middlemass) from the University of Sydney reported at the Nutrition Society of Australia (November 2005) that a pre-dinner drink tends to produce a ‘priming’ effect, flicking the switch from internal to external sources of fuel and keeping blood-sugar levels low. In one study, they gave healthy, young, lean people two standard glasses of beer, or wine, or gin and tonic or water to drink about an hour before eating a meal then they measured their blood glucose and insulin levels. They found that: ‘realistic amounts of beer, wine or gin reduce postprandial glycemia but not insulinemia’.
Glycemic Index of Foods