Hi!
Yes, there is a difference - the ready-made are 325ml while the ones you make up are 250ml, so the ready-made are bigger. However, they both have 230cal if you make up the shake with 250ml of semi-skimmed milk.
However - if you use water instead of milk for the made-up ones, you can shed 88 cals straight away.
I wouldn't worry - the ready-mades are not what was used on the Newcastle Study diet, and will contain a little bit more fat, but as far as calorie restricting goes - 3 x 230 = 690 cals. Make it up to 800 cals with your veg intake.
I hope you get on okay with it. I find the shakes okay and not too sweet (I've had both) but I am taking in much more than my normal amount of carbs - 35g carb in one made-up one out of a tin (a bit less without the milk), which is a whole day's worth! Strangely, the ready-made ones have only 26g carb.
I'm still eating an omelette for breakfast, with two shakes out of a tin if I'm at home, one ready-made and one out of a tin if I'm working, plus a whole heap of microwaved and/or roast veg for supper.
So far I'm okay and I haven't hit the cheese yet - but it's only my second day! :lol:
Viv 8)