I think if you're aiming for health related course at Uni, go for psychology because you are probably going to come across similarities which you would already be familiar with.
For example, when learning about the structure of the brain and the function of different areas or child behaviour and development + some other topics at Uni, the a level psych bunch had a little advantage.
A handful of med schools accept Psychology as an alternative science to one of Biology or Chemistry which if they do that, probably means something for their course (Manchester, Leicester, Keele, Sheffield...)
Psych is an essay heavy A level so you'll have to be confident with writing structured essays and are able to memorise content including facts, names (only those mentioned in the specification), evaluation points and incorporate it into a good essay answer relative to the context in the question.
The content is actually pretty fun too most of the time, depending on what your teacher picks from the list of topics. You get to learn about cool but unethical experiments, the reasons why people commit evil under orders and how we're all most likely one of those who would do so, how people develop preference for relationships, how it's a nightmare to bring up a child lol (This is my experience with AQA)