I applied for Dentistry but the back-up still applies, I put biomed at Newcastle on my UCAS form because there is the chance to apply for a transfer onto med/dent after 1st year which is competitive but possibly worthwhile (although I made sure the course sounded interesting too in case I ended up stuck on it).
I'd say pick a degree you'd find interesting, you could be stuck doing it for 3 years. There are plenty of healthcare related careers that aren't medicine but you'll be helping people and potentially saving lives, look into pharmacy, biomedical science, optometry etc. and see which you could see yourself doing as it may be you end up doing that instead of medicine for the rest of your life. Good luck, hopefully you won't need that back up!