I gained over a stone on a one week Holiday from ratting everything in sight -_- the amount of weight u put on will depend on the amount of stuff you eat. My advice is to enjoy yourself your on holiday u shouldn’t punish yourself by not eating what u want on holiday as you can always loose the weight easily when u come back. If you are worried about gaining weight maybe have a healthy ish lunch and breakfast so u can then treat urself with snack and dinner. Have a nice holiday x