Yes there is lots of evidence and more is coming out all of the time.
Most places that you get the injections from will also talk about weight gain afterwards too as it’s a known thing.
If you look on the pharmacy websites they’ll have it on there too.
And yes a lot of diets do lead to weight gain because you’re restricting yourself and then go back to bad habits.
But the difference with most other diets is that you are consciously restricting yourself and trying to change your mindset around food.
The injections quieten the food noise, reduce sugary cravings and in simple terms store less calories from the food that you are eating.
So when you come off of them the food noise and sugary cravings are going to be way worse because you’ve got used to not having them. And your metabolism will be back to its normal self.
Obesity costs the NHS millions every year and so if these injections led to long-term weight loss then it would be cheaper to give them to everyone who was overweight for 6months and be done.
Anyone who is obese I would say definitely try them because they can improve self esteem etc which leads to long term healthier eating and exercise.
But like with OP who only has a couple of stone to lose, it’s weighing up whether it’s worth it or not.
If you don’t have much weight to lose then perhaps stay on a low dose and just be very conscious of what you’re eating and exercising afterwards.