The food system and climate change: are plant-based diets becoming unhealthy and less environmentally sustainable?

Jennie Macdiarmid* (Corresponding Author)

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

18 Citations (Scopus)
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A plant-based diet including small amounts of meat is the foundation for healthy sustainable diets, which will have co-benefits for health, climate and the environment. Studies shows that some of the barriers to making this dietary change and reducing meat consumption are perceptions that plant-based diets are inconvenient, it takes too much time and skills to prepare meals and ingredients are expensive. The food environment, however, is changing and the industry is responding with the exponential increase in the market of highly processed, convenient and cheap plant-based foods. This overcomes some of the barriers, but there is concern about whether they are healthy and environmentally sustainable. Plant-based foods have a halo effect around health and the environment, but many being produced are ultra-processed foods that are high in energy, fat, sugar and salt and have a higher environmental impact than minimally processed plant-based foods. The trend towards eating more highly processed plant-based convenience foods is a concern with regard to both public health and the target of reducing greenhouse gas (GHG) emissions. The 'modern day' plant-based diet emerging is very different to a more traditional one comprising pulses, vegetables and wholegrain. Studies show that those who are younger and have been a vegetarian for a shorter duration are eating significantly more ultra-processed plant-based foods. While there is a place for convenient, desirable and affordable plant-based food to encourage dietary change, care should be taken that this does not subconsciously set a path which may ultimately be neither healthy nor sustainable.

Original languageEnglish
Pages (from-to)162-167
Number of pages6
JournalProceedings of the Nutrition Society
Issue number2
Early online date11 Oct 2021
Publication statusPublished - May 2022
EventSummer Conference 2021: Nutrition in a changing world - Online conference hosted by the University of Southampton, Southampton , United Kingdom
Duration: 6 Jul 20218 Jul 2021

Bibliographical note

Financial Support
There was no specific funding associated with the preparation of this manuscript. The author’s time is primarily funded through the Scottish Government Rural and Environment Science and Analytical Services.


  • Climate change
  • Food systems
  • Health
  • Plant-based diet
  • Ultra-processed food
  • MEAT


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