Modest changes to meat and dairy consumption could help Scotland meet climate goals while improving health and nutrition, research shows.
A modeling study found that using vegetables, beans and eggs instead of processed and unprocessed meat and dairy could deliver environmental and health benefits without increasing the overall cost of diets.
Experts say making healthier, more sustainable food options more accessible and convenient could help accelerate progress towards climate and public health goals.
Scientists from the University of Edinburgh assessed 33 different ways of meeting the UK Climate Change Committee's recommendations for sustainable diets.
The research examined the impact of dietary changes on greenhouse gas emissions, land and water use, nutrient intake, diet costs and health conditions including type 2 diabetes and cardiovascular disease.
Across all scenarios modeled, reductions in meat and dairy consumption were associated with improvements in health outcomes and environmental indicators, the study found.
Researchers found that even small, gram-for-gram substitutions in everyday meals such as sandwiches and pasta dishes could produce meaningful long-term benefits for both people and the planet.
Replacing some meat with a variety of alternative foods did not adversely affect nutrient intake. While lower dairy consumption could considerably reduce iodine intake among some groups, this could be addressed through iodine fortification of plant-based dairy alternatives, experts say.
The findings challenge perceptions that more sustainable diets are necessarily more expensive, with most dietary changes having little impact on overall food costs.
The study suggests that targeting people who consume the largest amounts of processed and unprocessed red meat could deliver the greatest benefits. Rather than reducing consumption evenly across the population, helping high consumers move towards lower intakes was predicted to prevent almost 60,000 cases of type 2 diabetes over a 10-year period while also achieving greater environmental gains.
All modeled dietary pathways resulted in lower greenhouse gas emissions as well as reductions in land and water use.
The research also found that emissions associated with food consumption by adults in Scotland, including the carbon footprint of imported food, exceed emissions from agricultural production in Scotland. The findings highlight the importance of dietary change alongside efforts to reduce emissions from agriculture.
Dr. Joe Kennedy, from the University of Edinburgh’s Division of Global Agriculture and Food Systems, said: "The findings show that modest, realistic dietary changes, when scaled across a population, can deliver substantial benefits to people and the planet. Making healthier, sustainable options more available and convenient will be key to enabling such change."
The study was carried out in collaboration with colleagues from the University of Oxford and Food Standards Scotland.
The study is published in the journal Nature Food. It was funded by the Wellcome Trust and Food Standards Scotland.