Nutrition science is defined globally as the study of food systems, foods and drinks, and their nutrients and other constituents; and of their interactions within and between all relevant biological, social and environmental systems.(1) Outside the biological sciences, which are core to practice in nutritional therapy, applied nutritionists have knowledge, skills and understanding which underpin competence in areas which may include inter alia epidemiology, public health practice, food technology and development, food safety, food law, ecological and environmental sustainability, economics, catering, journalism, politics and social science. The National Occupational Standards (NOS) for Nutritional Therapy cover clinical practice only. Practitioners working in applied nutrition have qualifications, training and experience additional to those required to meet the NOS for clinical practice.

(1) http://www.iuns.org/features/05-09%20NNS%20Declaration.pdf