The association is a registered charity and is a custodian of the United Kingdom Voluntary Register of Nutritionists (UKVRN)[1] Its purpose is to "protect and benefit the public by defining and advancing standards of evidence-based practice across the field of nutrition and at all levels within the workforce".

[6] All registrants on the UKVRN have had to provide evidence of their training and professional nutrition experience.

Registered Associate Nutritionists (post-nominals: ANutr) are recent graduates, who have been able to demonstrate a sound foundation of knowledge and understanding in nutrition science, and are working towards gaining sufficient experience within a specialist area to become a Registered Nutritionist (RNutr).

[8][9] Registered Nutritionists (post nominals RNutr) have been assessed as having demonstrated that they have met rigorously applied knowledge, understanding and practice core competencies set by the AfN.

[10] Fellows (FAfN) have been Registered Nutritionists (RNutr) for at least five years and have been recognized by their peers as have made a significant and sustained contribution to the advancement of nutrition practice, research or education at a national or international level.