The Riddet Institute is one of New Zealand’s Centres of Research Excellence (CoRE) which is hosted by Massey University. His research interests include nutrition for health, sustainable nutrition, and physiology and metabolism.

At the Riddet Institute, Warren leads several programmes including the Sustainable Nutrition Initiative® (SNI) and the MBIE-funded programmes, New Zealand Milks Mean More (NZ3M) and Kai anamata mō Aotearoa – exploring future food system scenarios and impacts. Warren is also a Principal Investigator in the Riddet Institute CoRE Research programme and an Associate Investigator in the HVN National Science Challenge priority research programmes’, Healthy Digestion, and Infant Health.

Warren has been elected to a number of international committees including the Food and Agriculture Organization of the United Nations (FAO) to be a member of the International Scientific Advisory Committee guiding the process leading to a comprehensive and evidence-based global assessment of the contribution of livestock to food security, sustainable food systems, nutrition, and healthy diets, and to represent NZ as a member of the World Farming Organisation (WFO) Scientific Council by Federated Farmers NZ.