Am sure they will be fine, and you would be best off giving them bland food tonight. in regards to reducing their food, it is a very good idea, and sadly not one most people think off. Pet food says cats regulate their intake, but if that is the case, how come a large percentage of the cat population is obese? It is much easier to keep on top of your cats weight now by controlling their food rather than trying to make an obese cat diet - take it from someone who has taken in a few overweight cats and struggled to get them down to a manageable weight - and as with humans, there are risks to being obese.