Hi IantheH,
Since it's the fermentation of sugar into alcohol that does the business, then yes it's probably true that the lower the alcohol, the more the sugar. The highly alcoholic spirits won't raise your blood sugar at all, which is excellent news if you like your malt whisky. :wink: Beers at around 5% alcohol will definitely raise your bs, while wines at 12-15% will too, but very much less.
The fall in blood sugar later is partly down to the alcohols ability to paralyse the liver, preventing it from generating glucose for a while.
Cheers!
fergus