HI SL, ;lots of questions there!! :)
First, if you're speaking of the UK< face it, non-EU students have an exceptionally hard time. You are not eligible for research council funding, you pay very high fees.
Second, people still do it. As I've said elsewhere I've given up full fellowships in the US, to work with my supervisor here in the UK, at less than half the money. The rest in the first yr is self funded, though I have a research studentship for a little more than half of my tuition. next yr on i wil work, and lets see how it goes.
Third, there might still be positions available for nonEU people, but i dont think they are gonna be wholly funded inclusive of livign costs. If you are planning to stay in London, natural costs are higher.
Fourth, as far as your subject goes, both nutrition and socio are highly specialised fields to "enter", unlike media, or management and many other field which are great and challenging places to enter from diverse disciplinary histories. So, considering the field you want enter is itself specialised please take a moment to think carefullly before you decide. You dnt want to spend a hellish amt of time doing groundwork in socio, when you are prepard from nutri (and not something close liek anthro or psycho or history etc). Of course, the choice is upto you, and maybe yous hould after all make the change.
best!
