In rat studies with mounjaro, some rats developed cancer. However rats have glp-1 receptors on their thyroid. Humans do not. There isn't a single case or link between mounjaro and increased cancer risk. In fact there are many recently published studies that show it reduces the risk of many cancers, independent of weight loss. It also improves cardiovascular outcomes and reduces mortality in general. There are other risks, especially if it's abused, but you'll have to weigh those up against the risks associated with obesity. It's a personal decision, but should be well informed by the science and perhaps the experience of others.
Also mounjaro is not offlabel for weight loss. It's prescribed specifically for obesity in the UK. The US is slightly different, the brand name for weight loss there is zepbound. But it's the same drug.
Mounjaro is a GIP and GLP-1 medication, whereas weegovy/ozempic is GLP-1 only. I think at certain doses, mounjaro is more effective according to studies. And it seems side effects on Mounjaro are not as bad as weegovy - anecdotally at least.
I've been on Mounjaro for 10 weeks and it's kind of like what a nicotine patch is to smoking. You still have to do the work - eat right, exercise, drink water, get your vitamins etc, but it makes it easier to do, and easier to sustain for the long period of time you have to in order to go from obese to a healthy weight. I have tried and failed to lose weight for years. The only thing that worked before was very low carb but it made me miserable and was so unhealthy/disordered eating and unsustainable. I know I wouldn't have been able to lose the weight I've lost in the past 2 months without mounjaro. And it's coming off at a sensible rate of around 1.5 - 2.5 lbs per week on average. It's not a "quick fix".
When I was chatting to my GP about it, he said that it would make my brain like a naturally slim persons - and it does. It reduces all that food noise. It also does so much more like helps regulate cycles for some women or balances out mood/reduces anxiety for some too.
But, it's a serious drug, and sometimes the side effects are no joke. Do your research. What do medical professionals say about it online? Ignore pseudoscience snake oil salespeople like Jillian Michaels or celebs who take it to get super skinny.
Have a look at the first post on the main Mounjaro thread - I think it's thread 12. There's lots of info and links on there.