9.1 How might we define sustainable and healthy eating patterns (SHEPs)?

9.1.1 General considerations for defining SHEPs

General considerations for defining SHEPs

  • ‘Sustainable’ is a multifaceted concept.
  • Often definitions focus only on environmental aspects.
  • And within the environment, often only GHG emissions are considered, although land use and water also receive attention.
  • Other aspects of sustainability are less well researched.

9.1.2 FAO definition of sustainable diets

The FAO describes the broad characteristics of sustainable and healthy eating patterns

Sustainable diets are “those diets with low environmental impacts which contribute to food and nutrition security and to healthy life for present and future generations. Sustainable diets are protective and respectful of biodiversity and ecosystems, culturally acceptable, accessible, economically fair and affordable; nutritionally adequate, safe and healthy; while optimizing natural and human resources.”

This FAO definition encompasses:

  • Nutrition and health
  • Biodiversity protection
  • Optimisation of natural and human resources
  • Affordability and availability
  • Cultural relevance

This implies that SHEPs should provide the required energy and nutritional content (see Chapter 7 [hyperlink] for more on the links between food and health), not negatively impact biodiversity (for example impacts such as deforestation and negative land-use consequences, overexploitation of marine biodiversity – see Chapter 5 [hyperlink]), optimise natural resources (for example, optimal food production without causing unacceptable greenhouse gas emissions– see Chapter 4) and support human livelihoods (for example, respect working lives of those whose livelihoods depend on food systems), be affordable and available (see Chapter 4 and Chapter 7  for more on food security) and be culturally appropriate and acceptable.

This definition is therefore  very comprehensive, encompassing many aspects of sustainability (environmental, socio-economic and cultural) but:

  • It is not clear what such a diet might look like ‘on a plate’
  • It is not clear what metrics could be used to assess whether a diet is sustainable or not
  • There is therefore a need for metrics to assess how a diet performs across a range of sustainability indicators.

This chapter therefore discusses the research base and evidence pointing towards what SHEPs might look like ‘on the plate.’

9.1.3 How might we measure and identify SHEPs?

How might we measure SHEPs?

Dimensions of sustainability

How can we measure them?

Environmental (including climate change, water use and pollution, fossil fuel use, air pollution, land use change and biodiversity loss)

Some of these are covered by environmental life cycle assessments (LCA) and by evolving work on water footprinting, but not all. See Chapter 2 [hyperlink] for more on LCA.

Food security (availability, access, utilisation, stability)

Food security indicators available and evolving. See Chapter 7 [hyperlink] for more on food security.

Nutrition

Energy, protein, fat, zinc, calcium, iron etc.; nutrient density indicators; health outcomes (non-communicable diseases). See Chapter 7 [hyperlink] for more on the link between food and health.

Livelihoods, jobs and economic development

These may include incomes, the retail price index, working conditions, contribution to GDP. Evolving metrics, some certification schemes exist. Social LCA is an evolving research area (see Chapter 2 [hyperlink]).

Animal welfare

Some certification schemes exist, but different opinions exist as to what constitutes good welfare in different contexts.

Culture

This is a very under-researched and under-considered area in relation to sustainability (see Chapter 10  [hyperlink] for more on cultural factors).

9.1.4 How has research attempted to measure and identify SHEPs?

How has research attempted to measure SHEPs?

Environmental impacts

Research into environmental impacts of eating patterns has largely focused on GHGs. There is also some research focusing on water footprints, land-use and energy-use. GHG are often used as a proxy for environmental impacts as a whole, although there can be conflicts between, for example, low GHG and water-use in water stressed areas.

Nutrition and health outcomes

Measuring the nutritional quality of a diet is complex. Some research focuses on the macro and micronutrient content of different diets. Other studies focus on the actual health outcomes associated with different diets and eating patterns.

Dietary Comparisons

Dietary comparisons have been made in relation to both health and environmental impacts. These have often compared models of different types of diets (such as vegetarian diets) with actual and recommended diets. Some research has looked at different kinds of real-life diets rather than modelled diets.

A lot of work has been done to try and define SHEPs based on various different comparative approaches. Most of them focus on comparing the environmental aspects of different diets (for example “average diets” compared to “vegetarian diets” or “recommended diets”), with GHGs the most common environmental metric used.

Assessments of nutritional quality and health outcomes can be quite basic (protein, energy, fat, fruit and veg) or complex (including assessment of micronutrient contents and nutrient density). Some research has looked at the link between different diets, environmental impacts and health outcomes such as heart disease. This chapter provides a summary of the research findings and the relationships between changes in eating patterns, health and environmental impact.