[Aluback]

I know a lot of people here are probably knowledgeable about nutrition so I'm going to ask this here.

I've been dieting trying to lose weight for kendo, my diet generally consists of cereal/no-fat milk and a bannana for breakfast, then throughout the day every hour or two I'll eat an apple or some raw baby carrots for snacks then a sensible dinner.

Well, on certain days when I'm really pushing to lose weight I'll eat an extremely light dinner; for instance, yesterday I ate a 6" Subway chicken sandwich with no cheese and no mayo. The thing is though on the days I eat an extra light dinner I lose no weight, when I eat a more normal dinner (tonkatsu for instance at my favorite Japanese restaurant) I almost consistently lose weight.

Does anyone know what i'm doing wrong on the days when I eat light that's stopping me from losing?