The Association for Nutrition has developed a model which gives the core competencies for people working in the field of nutrition including GPs, nurses, health visitors, dietitians, nutritionists, teachers, community workers, and personal trainers. It is well worth a look.
AfN are in the process of looking at courses to see which competencies they meet in order to develop a list of training available, and they are working on an online assessment tool to help workers identify where they need more training.
Great piece of work.