Has anyone gone via a private GP and then prescription? Or do some of the providers include full consultations? Do I need bloods tested before starting? Or an all over MOT?!
Not many will be using a private GP due to the additional expense, you might find a few people but it's not very usual. What do you mean by a "full consultation"? When you apply online you give your full medical details, and then you are screened for any contraindications or issues. You also submit photos, video or do a live video consult to check your weight and height. Once you've submitted the form, the consultation is then reviewed and approved/rejected by the prescribing pharmacist or doctor.
You don't need blood tests before starting. Some online pharmacies offer them, Numan do I think, as well as SheMed. You can get a home blood test privately online as well if you like. You also don't need an "all over MOT", although again, if you want one you can get one done privately at any time.
Do I need to inform my GP that I'm starting it or would I just update at next appointment next time I'm there about something else?
The online pharmacies will ask for permission to notify your GP. Typically they send a letter that outlines what you've been prescribed, and when the GP surgery gets the letter they just update your notes with the prescription info. You can check that on the NHS app, if you have it.
Do you take a lot of supplements if food intake is much lower?
You don't need to take a lot of supplements. I always take a decent multivitamin so continue with that. People will recommend all sorts of things, but none are essential, it's personal choice. Your food intake should not be so low as to make it impossible to get sufficient nutrition, long term.
Finally, are there many threads about people who have stopped Mounjaro (at target weight) and broadly sustained weight loss? Or does it really need to be a lifelong commitment? At £200ish/month (at today's prices!) it's a huge cost.
There is a long running thread for those who are maintaining. Some have stopped taking it, some are taking various levels of doses for the longer term. It's personal to each individual.
https://www.mumsnet.com/talk/weight-loss-injections/5252687-youve-reached-your-goal-weight-come-chat-about-maintenance-not-regaining-going-cold-turkey-or-titrating-down?utm_campaign=thread&utm_medium=share
BTW, it really doesn't have to cost £200 per month, that would be at the very expensive end of suppliers. I haven't paid as much as that at any point. The medication is the same regardless of where you get it from, so you may as well look for the cheaper/est options for where to get it from. The lower doses are usually around the £100 mark, and even the higher doses can be found for under the £200 mark.