Sustainable diets and sustainable food systems are increasingly explored by diverse scientific disciplines. They are also recognised by the international community and called upon to orient action towards the eradication of hunger and malnutrition and the fulfilment of sustainable development goals. The aim of the present paper is to briefly consider some of the links between these two notions in order to facilitate the operationalisation of the concept of sustainable diet. The concept of sustainable diet was defined in 2010 combining two totally different perspectives: a nutrition perspective, focused on individuals, and a global sustainability perspective, in all its dimensions: environmental, economic and social. The nutrition perspective can be easily related to health outcomes. The global sustainability perspective is more difficult to analyse directly. We propose that it be measured as the contribution of a diet to the sustainability of food systems. Such an approach, covering the three dimensions of sustainability, enables identification of interactions and interrelations between food systems and diets. It provides opportunities to find levers of change towards sustainability. Diets are both the results and the drivers of food systems. The drivers of change for those variously involved, consumers and private individuals, are different, and can be triggered by different dimensions (heath, environment, social and cultural). Combining different dimensions and reasons for change can help facilitate the transition to sustainable diets, recognising the food system's specificities. The adoption of sustainable diets can be facilitated and enabled by food systems, and by appropriate policies and incentives.

The globalisation of agrifood systems is a mega-trend with potentially profound nutritional implications. This paper describes various facets of this globalisation process and reviews studies on nutritional effects with a particular focus on developing countries. Results show that global trade and technological change in agriculture have substantially improved food security in recent decades, although intensified production systems have also contributed to environmental problems in some regions. New agricultural technologies and policies need to place more emphasis on promoting dietary diversity and reducing environmental externalities. Globalising agrifood systems also involve changing supply-chain structures, with a rapid rise of modern retailing, new food safety and food quality standards, and higher levels of vertical integration. Studies show that emerging high-value supply chains can contribute to income growth in the small farm sector and improved access to food for rural and urban populations. However, there is also evidence that the retail revolution in developing countries, with its growing role of supermarkets and processed foods, can contribute to overweight and obesity among consumers. The multi-faceted linkages between changing agrifood systems and nutrition are a new field of interdisciplinary research, combining agricultural, nutritional, economics and social sciences perspectives. The number of studies on specific aspects is still limited, so the evidence is not yet conclusive. A review at this early stage can help to better understand important relationships and encourage follow-up work.

Global demand for meat and dairy products has increased dramatically in recent decades and, through a combination of global population growth, increased lifespan and improved economic prosperity in the developing world will inevitably continue to increase. The predicted increases in livestock production will put a potentially unsustainable burden on global resources, including land for production of crops required for animal feed and fresh water. Furthermore, animal production itself is associated with greenhouse gas production, which may speed up global warming and thereby impact on our ability to produce food. There is, therefore, an urgent need to find methods to improve the sustainability of livestock production. This review will consider various options for improving the sustainability of livestock production with particular emphasis on finding ways to replace conventional crops as sources of animal feeds. Alternatives, such as currently underutilised crops (grown on a marginal land) and insects, reared on substrates not suitable for direct consumption by farm animals, represent possible solutions. Coupled with a moderation of excessive meat consumption in wealthier countries, such strategies may secure the long-term sustainability of meat and milk production and mitigate against the adverse health effects of excessive intake.

While we state it seems unthinkable to throw away nearly a third of the food we produce, we still continue to overlook that we are all very much part of this problem because we all consume meals. The amount of food wasted clearly has an impact on our view of what we think a sustainable meal is and our research suggests food waste is a universal function that can help us determine the sustainability of diets. Achieving sustainability in food systems depends on the utilisation of both culinary skills and knowledge of how foods make meals. These are overlooked by the current food waste debate that is concerned with communicating the problem with food waste rather than solutions to it. We aim to change this oversight with the research presented here that demonstrates the need to consider the role of food preservation to reduce food waste and the requirement for new marketing terms associated with sustainability actions that can be used to stimulate changes in consumption behaviours. We have chosen frozen food to demonstrate this because our research has shown that the use of frozen foods results in 47 % less household food waste than fresh food categories. This has created a step-change in how we view food consumption and has stimulated consumer movements that act across different products and supply chains to enable the consumption of the sustainable meal.

‘Wholesome Nutrition’ is a concept of sustainable nutrition that was developed at the University of Giessen in the 1980s. In this concept, health and the ecologic, economic, social and cultural dimensions of nutrition are equally important. In 1992 at the UN-Conference on Environment and Development in Rio de Janeiro the definition of ‘Sustainable Development’ comprised the dimensions environment, economy and society. Additionally to these three ‘classical’ dimensions of sustainability, we included ‘health’ as the fourth dimension because nutrition has far reaching effects on human health. The fifth dimension, ‘culture’, became part of the sustainability dialogue since many years; the respective cultural background influences food habits. Presently, mankind has to cope with huge global challenges such as poverty and food insecurity in low-income countries as well as climate change. Therefore the objective is to identify prospects for actions to respond to these global challenges. The concept of ‘Sustainable Nutrition’ analyses the food supply chain at all stages from input-production and primary production to processing, distribution, preparation, consumption and waste disposal. The present analysis leads to the following seven principles: preference of plant-based foods, organic foods, regional and seasonal products, preference of minimally processed foods, Fair Trade products, resource-saving housekeeping and enjoyable eating culture. This concept is based on holistic thinking and has the potential to reduce the global challenges in the field of nutrition. Scientists, stakeholders, multipliers and consumers are asked to consider environmental, economic, social and cultural aspects in addition to the biological (health) aspects.

Current dietary assessment methods including FFQ, 24-h recalls and weighed food diaries are associated with many measurement errors. In an attempt to overcome some of these errors, dietary biomarkers have emerged as a complementary approach to these traditional methods. Metabolomics has developed as a key technology for the identification of new dietary biomarkers and to date, metabolomic-based approaches have led to the identification of a number of putative biomarkers. The three approaches generally employed when using metabolomics in dietary biomarker discovery are: (i) acute interventions where participants consume specific amounts of a test food, (ii) cohort studies where metabolic profiles are compared between consumers and non-consumers of a specific food and (iii) the analysis of dietary patterns and metabolic profiles to identify nutritypes and biomarkers. The present review critiques the current literature in terms of the approaches used for dietary biomarker discovery and gives a detailed overview of the currently proposed biomarkers, highlighting steps needed for their full validation. Furthermore, the present review also evaluates areas such as current databases and software tools, which are needed to advance the interpretation of results and therefore enhance the utility of dietary biomarkers in nutrition research.

Recent re-evaluations of dietary reference values (DRV) for vitamin D have established intake requirements between 10 and 20 µg/d. National nutrition surveys indicate that habitual mean intakes of vitamin D in the population are typically in the range 3–7 µg/d. As vitamin D supplementation will not be effective at a population level because the uptake is generally low, creative food-based solutions are needed to bridge the gap between current intakes and these new requirement values. The overarching aim of this review is to highlight how food-based solutions can have an important role in bridging this gap and counteracting vitamin D inadequacy in Europe and elsewhere. The present review initially briefly overviews very recent new European DRV for vitamin D and, while not in agreement on requirement estimates, how they point very clearly to the need for food-based solutions. The review discusses the need for traditional fortification of foods in the dairy and other sectors, and finally overviews recent advances in the area of biofortification of food with vitamin D. In conclusion, increasing vitamin D intakes across the population distribution is important from a public health perspective to reduce the high degree of inadequacy of vitamin D intake in Europe. Fortification, including biofortification, of a wider range of foods, which accommodate diversity, is likely to have the potential to increase vitamin D intakes across the population distribution. Research has had, and will continue to have, a key role in terms of developing food-based solutions and tackling vitamin D deficiency.

The aim of this review was to determine the impact of the fatty acid desaturase (FADS) genotype on plasma and tissue concentrations of the long-chain (LC) n-3 PUFA, including EPA and DHA, which are associated with the risk of several diet-related chronic diseases, including CVD. In addition to dietary intakes, which are low for many individuals, tissue EPA and DHA are also influenced by the rate of bioconversion from α-linolenic acid (αLNA). Δ-5 and Δ-6 desaturase enzymes, encoded for by FADS1 and FADS2 genes, are key desaturation enzymes involved in the bioconversion of essential fatty acids (αLNA and linoleic acid (LA)) to longer chained PUFA. In general, carriers of FADS minor alleles tend to have higher habitual plasma and tissue levels of LA and αLNA, and lower levels of arachidonic acid, EPA and also to a lesser extent DHA. In conclusion, available research findings suggest that FADS minor alleles are also associated with reduced inflammation and CVD risk, and that dietary total fat and fatty acid intake have the potential to modify relationships between FADS gene variants and circulating fatty acid levels. However to date, neither the size-effects of FADS variants on fatty acid status, nor the functional SNP in FADS1 and 2 have been identified. Such information could contribute to the refinement and targeting of EPA and DHA recommendations, whereby additional LC n-3 PUFA intakes could be recommended for those carrying FADS minor alleles.

Vitamin D is obtained by cattle from the diet and from skin production via UVB exposure from sunlight. The vitamin D status of the cow impacts the vitamin D content of the milk produced, much like human breast milk, with seasonal variation in the vitamin D content of milk well documented. Factors such as changes in husbandry practices therefore have the potential to impact the vitamin D content of milk. For example, a shift to year-round housing from traditional practices of cattle being out to graze during the summer months and housed during the winter only, minimises exposure to the sun and has been shown to negatively influence the vitamin D content of the milk produced. Other practices such as changing dietary sources of vitamin D may also influence the vitamin D content of milk, and evidence exists to suggest genetic factors such as breed can cause variation in the concentrations of vitamin D in the milk produced. The present review aims to provide an overview of the current understanding of how genetic and environmental factors influence the vitamin D content of the milk produced by dairy cattle. A number of environmental and genetic factors have previously been identified as having influence on the nutritional content of the milk produced. The present review highlights a need for further research to fully elucidate how farmers could manipulate the factors identified to their advantage with respect to increasing the vitamin D content of milk and standardising it across the year.