When she was applying for post-grad medicine, I remember her saying her goals were not actually to become an NHS doctor but to become some sort of alternative doctor where she can use veganism/whole foods to cure people

. I have a feeling this is what she will want to do if she becomes a registered nutritonist. No way will she be working for the NHS. She will probably try to be self employed like she is with her tutoring. Giving meal plans and nutritional advice over Skype/Zoom and charging extortionate prices.
I get that following a whole foods diet can have medicinal benefits, especially for those with diseases that are caused by poor diet. But this information is common knowledge that can be found for free with a quick Google search. She will be robbing these vulnerable people of their money.