7.1 How are food systems and health connected and influenced?

7.1.1 Connections between food and health

Some of the links between food and health are shown below.

Food and health are connected in many ways

Health concern

The food system’s role

Environmental health risks

Different environmental health risks exist relating to water and air pollution, in addition to risks to food systems from climate change (see Chapter 6 for climate change impacts on food systems). Manure and agrochemicals cause water pollution which may lead to acute poisoning and long term harms (e.g. cancers, reproductive disorders); field burning and intensive livestock systems cause air pollution and respiratory illnesses; ecosystem damage and climate change (to which food systems contribute) alters patterns of disease and pest movements, leads to loss of resilience, and reduced ability to adapt to future climate shocks.

Food security, nutrition and associated diseases

Critical factors include the type and quantity of food produced, the way it is processed and marketed, its price and availability, access to adequate storage and cooking, and many other factors. These variously give rise to: undernutrition (protein and/or energy deficiencies); overconsumption (leading to obesity and associated chronic diseases); and micronutrient deficiencies.

Infectious diseases and injuries

Zoonotic diseases; food pathogens from livestock production or inadequate storage; antimicrobial resistance especially from intensive livestock systems;  vector borne diseases from agri-induced land use change and water infrastructure; pesticide and agrochemical poisonings; occupational hazards (heat stress, injuries, UV radiation, and other unsafe working conditions).

Health equity impacts

Health risks and benefits are unevenly distributed among rich and poor, rural and urban, women and men, land owners and the landless, arising from factors such as affordability, access, time and knowledge.

7.1.2 Influences on food consumption

The influences on food consumption and associated health outcomes are complex and multiple

  • The influences on food consumption are multiple.
  • Diet-related health outcomes are shaped by multiple social, economic, cultural and political factors.
  • These multiple influences on food consumption interact with other factors (from environmental through to genetic) to influence health outcomes.
  • The affordability of food has a critical influence on health outcomes.

Influences on diet

Garnett, T. and Finch, J. (2016, unpublished).


The health impacts of consumption patterns are influenced by many factors, not just food security. These include: levels of economic development, agricultural policy, pricing strategies, changes in how food is produced and distributed, marketing and media, values and aspirations, nutritional knowledge and access to information, and traditional attitudes to food and health. The role of policy is crucial – it shapes the overarching social, infrastructural and economic influences on consumption and the extent to which health consequences are addressed.

Nutrition-related health outcomes are therefore impacted by factors other than just food security, being multi-level, multi-sectoral, and multi-cultural. Some of these factors, relating to socio-economic status and lifestyles are discussed later in this chapter.

7.1.3 The importance of the socio-economic context

This diagram, often known as the social-ecological model of public health, shows that the health of any individual is influenced by a huge range of factors from individual genetics, sex and race through to the broader social, economic and political conditions that influence our lives.

These multiple influences on food consumption interact with other factors (from environmental through to genetic) to influence health outcomes


Based on Institute of Medicine (2003)

Food affordability is critical

Poor people spend more of their budget on food.

This means less for education, housing and health, increasing overall vulnerability.

Economist (2013)

The proportion of income that is spent on food varies widely across countries and within populations and is linked to inequality of incomes. Populations who spend a high proportion of their income on food are more vulnerable to supply and price changes in food, but additionally have less disposable income to spend on, for example, education and health. They can also be more vulnerable to sanitation risks, lack of safe drinking water and related illnesses. This poverty trap exacerbates health outcomes; poorer populations are more food insecure and more vulnerable to connected health problems.