The nutritional loss of food loss and waste and the environmental cost of inadequate diets
A new study by WASTEWISE, led by partners at Agroscope, presents a novel methodological framework to integrate nutritional and dietary dimensions into the life cycle assessment (LCA) of food loss and waste, addressing a gap in current environmental assessment practices.
While food loss and waste is typically assessed in terms of quantity and sometimes environmental impacts, such as the inefficient use of land, water, and energy in food production, it also has important nutritional implications. Nutritional losses occur at each stage of food value chains, from farm to table, as a result of food being lost or wasted, or through changes in nutritional quality that occur during storage or processing, such as nutrient degradation. At the same time, overconsumption represents a form of food waste: while it does not provide additional nutritional benefits, it carries unnecessary environmental burdens and is linked to overweight, obesity, and non‑communicable diseases.
In the study, three European supply chains were analysed to assess nutritional losses associated with food loss and waste and side streams: wheat with a focus on its derivatives pasta, bread and pastry; fresh tomatoes and tomato sauce; and bovine meat. Nutritional losses were quantified in absolute terms, in relation to dietary reference intakes (DRVs) and through food-group specific nutritional density indicators. In parallel, food overconsumption and underconsumption were quantified as deviation from national food-based dietary guidelines for Italy, Switzerland, and Sweden. In each country, actual and recommended diets were also compared in terms of energy and nutritional adequacy. Finally, the potential environmental implications (greenhouse gas emissions) of shifting from the actual to the recommended diet were evaluated for Italy as an illustrative case study.
Researchers found substantial nutritional losses embedded in all the three supply chains investigated, particularly in sidestreams and by-products, such as wheat bran and germ, tomato pomace, meat offal and animal blood. These are often more nutrient-dense than food loss and waste and could cover a large share of the population’s nutrient requirements, including those for nutrients at risk of deficiency, such as dietary fibre, vitamin B12 and iron. As they are usually diverted for non-food uses, side streams are excluded from conventional food waste accounting, representing hidden nutritional losses with concrete valorisation opportunities. Redirecting FLW and side streams towards human consumption would preserve their nutritional value and potentially reduce environmental impact. The environmental benefit depends on the substitution pathway and LCA approach, but becomes clearer under a nutritional LCA framework. The researchers emphasised the importance of nutritional indicators in informing decision-making at multiple levels and in future nLCA applications in the field of FLW and food systems.
Regarding overconsumption, the study confirms it as a major inefficiency in all the selected countries, with plant-based food groups being underconsumed systematically and meat, animal fats and discretionary products (such as sweets and alcoholic beverages) being overconsumed consistently. For example, applying an energy- and nutrient-corrected functional unit showed that aligning the Italian diet with national dietary guidelines could significantly reduce greenhouse gas emissions while improving nutritional adequacy.
While these findings offer important insights, the researchers note that the studied contexts represent a limited sample that cannot be generalised to other food systems. To build on these preliminary conclusions, the team outlines key directions for future research to further refine combined nutritional and environmental metrics for policy action.
