Yeah, I was wondering about this the other day... when calculating 100g leeks online and it came back as 12.6g ...
Just checked my Gem Calorie counter book and it says:
Leeks, trimmed, chopped and boiled (100g): 21cal, 1.2g protein, 2.6g carb, 0,7g fat and 1.7g fibre.
Cheers.