Shifting Towards Sustainable Diets – how dietitians can help

Originally published in Dietetics Today, the British Dietetic Association members’ magazine

Setting the scene – our unsustainable food system

Our current food system is unsustainable, and it is ‘distorted by inequalities of access.’ We have sufficient food to feed the current population of over seven billion people, yet half of the worlds population is malnourished, with the combined burdens of micronutrient deficiencies, hunger and obesity. Over the next 35 years the world’s population is not only expected to grow by a further two billion, but also increase in wealth and urbanisation. This will lead to an increased demand for ‘westernised’ dietary patterns, a dietary shift known as the ‘nutrition transition’, characterised by overconsumption and higher intakes of animal products, fat, sugar and processed foods. These dietary patterns are linked to increased non-communicable diseases, and their production is more resource-intensive, meaning that we may need to produce 60-70% more grain crops.

At the same time there will be a greater competition for diminishing natural resources, such as water, soil and land; set against a need to mitigate and adapt to the impacts of climate change. The entire food system is reported to contribute up to a third of human produced greenhouse gases, half of which come from the production of livestock. Other environmental impacts include depletion of fish stocks and loss of biodiversity.

Whole system change

All of this indicates a dire need for a whole system change, in order to ensure a food future that can provide a nutritionally adequate, sufficient and equitable diet for all. Four main areas for action are: improving the environmental efficiency of food production; ensuring equitable and affordable food distribution; reducing food waste, and shifting towards more ‘sustainable diets’. Each of these areas are important, but this paper will focus on ‘sustainable diets’; the area where dietitians can have the greatest impact.

What is a ‘sustainable diet’?

There is currently no single definition for a ‘sustainable diet’ and this is partly due to the difficulties in defining this term. For the purpose of this paper we use a definition that considers synergies between the ‘environment’ and ‘nutrition’, as this is where the main body of research exists, although more research is required to consider broader social and economic factors. Even with this narrower definition the issue remains complex, and depends not just on what food is eaten, but how and where it is produced and transported. This discussion can be explored further in Garnett 2014.

Broadly speaking, public health and environmental sustainability goals can align. They are not a perfect match, but there are some clear and consistent win-wins.  A few countries have started to incorporate environmental considerations into their dietary guidelines*, whilst in others, like the USA, such considerations have been controversially rejected. In the UK the Green Food Project, set up by the Department for Environment and Rural Affairs, drafted principles for more sustainable and healthy dietary patterns (detailed below). Designed to sit alongside the EatWell plate now renamed the EatWell Guide these emphasise certain food or purchasing considerations within the recommended food groups. However, these guidelines have no current official status.The greatest environmental benefits can be seen by reducing meat consumption and increasing the intake of plant-based foods; these changes can also align with nutritional advice. For example, this could reduce UK fat and protein intakes, which exceed daily recommended values, whilst increasing fibre intakes. 57% of men and 32% of women exceed the recommended 70g of red or processed meat a day** which is associated with an increased risk of cancer. There are health benefits associated with meat consumption and it is an important source of a number of micronutrients, however it is possible to achieve a complete, balanced diet with reduced or even no meat.What does this mean for dietitians?

As we are faced with an increasingly uncertain food future, there is an urgent need to take a sustainable ecological approach to our food system. The important role of dietitians as leaders in this emerging area was highlighted in a policy briefing on sustainable diets, published by the British Dietetic Association (BDA). It recommended that dietitians should be able to ‘reconcile the nutritional and environmental science to give consistent messages about a healthy sustainable diet’ in order to influence not only individuals, but also policy at local and national levels, and practice in workplaces and communities.

This is an emerging, complex scientific area which requires ongoing research. There is a need for a clear and usable definition of the term ‘sustainable diets’ and consideration of how this might incorporate broader economic and social goals. However there are already some clear messages we should be promoting, in order to protect the future of our food system, such as the need to moderate meat consumption, move towards more plant-based diets, and source fish sustainably.

In order to provide clear, consistent messages and raise awareness about the importance of sustainable diets, we should follow other countries’ lead and look to explicitly incorporate sustainability into our official dietary guidelines.* Whilst the launch of the new Eatwell Guide in March this year saw inclusion of the word sustainability, in particular in reference to fish and emphasised a more plant-based diet, there was no explicit messaging that will enable the public to draw the vital links between food, the environment and health. Dietitians could use their influential position to help bring about the stronger integration of sustainability messaging that is required. The BDA is already a member of the Eating Better Alliance, an alliance of almost 50 organisations, which are driving for this change. Research amongst American dietitians showed a lack of knowledge to be a major barrier to incorporating considerations of sustainability into their practice. No equivalent research has been conducted in the UK, but as this is a new area there is likely to be an educational need among practising professionals, as well as within undergraduate education, so that dietitians of the future are equipped with the skills and knowledge to take a broader, holistic, ecological approach to health. We cannot tackle this problem alone; change will require an interdisciplinary, multi-sectorial solution, -but we can play an important role in bringing about the urgent and necessary changes to our food system.

* Some countries including Sweden, Brazil and Germany have started to incorporate environmental sustainability into their national dietary guidelines.

For further reading on this see the new report Plates, Pyramids and Planet produced by Food Climate Research (FCRN) at Oxford University and Food and Agriculture Organisation (FAO). This report evaluates government-issued food-based dietary guidelines from across the globe, looking in particular at whether they make links to environmental sustainability as well as personal health.

** NatCen Social Research, MRC Human Nutrition Research & University College London Medical School, (2015a). National Diet and Nutrition Survey Years 1-4, 2008/09-2011/12. [data collection]. 7th Edition. UK Data Service.[Online] Available at: SN: 6533,