Ultra-processed foods consumption as a promoting factor of greenhouse gas emissions, water, energy, and land use: A longitudinal assessment

Background: Dietary patterns can produce an environmental impact. Changes in people's diet, such as the increased consumption of ultra-processed food (UPF) can not only influence human health but also environment sustainability. Objectives: Assessment of the impact of 2-year changes in UPF consumption on greenhouse gas emissions and water, energy and land use. Design: A 2-year longitudinal study after a dietary intervention including 5879 participants from a Southern European population between the ages of 55–75 years with metabolic syndrome. Methods: Food intake was assessed using a validated 143-item food frequency questionnaire, which allowed classifying foods according to the NOVA system. In addition, sociodemographic data, Mediterranean diet adherence, and physical activity were obtained from validated questionnaires. Greenhouse gas emissions, water, energy and land use were calculated by means of the Agribalyse® 3.0.1 database of environmental impact indicators for food items. Changes in UPF consumption during a 2-year period were analyzed. Statistical analyses were conducted using computed General Linear Models. Results: Participants with major reductions in their UPF consumption reduced their impact by −0.6 kg of CO₂eq and −5.3 MJ of energy. Water use was the only factor that increased as the percentage of UPF was reduced. Conclusions: Low consumption of ultra-processed foods may contribute to environmental sustainability. The processing level of the consumed food should be considered not only for nutritional advice on health but also for environmental protection. Trial registration: ISRCTN, ISRCTN89898870. Registered 05 September 2013, http://www.isrctn.com/ISRCTN89898870.