A discussion is currently going on in our house about this. We have looked online and get various answers. We have 4 adult cats (2 younger, 2 older - 2 larger sized). My ds will pour out a whole sachet each for 1 cat claiming that that is why they are made. I think that is over feeding mainly because they can always 'ask' if they want more. I tend to share a sachet between 2 cats so I give 1/2 sachet each. (By the way, we do buy tins as well for so many cats but get sachets as my teenagers are more likely to feed the poor cats after school this way!) It is difficult to monitor with 4 cats tbh - but our vet has told us to keep an eye on the weight of the eldest cat.