Milk. It seems to be significantly more detrimental to the diet than I thought it would be.
I was having two small 250ml lattes with whole milk per day, thinking it wasn't the worst thing. But I found myself getting really very hungry despite eating big compliant meals otherwise. Then it occurred to me that the milk could have been causing the problem, since it apparently causes lots of insulin to be produced. Because I was so hungry I ended up failing on the diet by mid afternoon.
Black coffee only today and I feel fine, no snacks, and not especially hungry either.

