For the first time, Norwegian researchers have calculated what effect the average Norwegian diet has on the climate and environment and have studied the potential benefits for the climate and environment if we start following a diet in line with existing dietary guidelines.

"When we collate dietary, climate and environmental data, we discover a unique platform for change," says the leader of the NOR-Eden Project, Professor Lene Frost Andersen.

The study of these collated data shows that if we change our diet so that it is in line with current guidelines, this will result in about 15% lower greenhouse gas emissions than our present eating habits produce. It would also lead to improvements in several other environmental indicators.

This entails eating less red meat, dairy products, sugary drinks, sweets and snacks and more wholegrain products, nuts, fruit and vegetables.

"It is important to provide Norwegian evidence on the connection between diet and sustainability. Many other countries have carried out similar studies, but since there is so much variation in environmental data from country to country, it is beneficial to have Norwegian data.

"And our findings confirm that our Norwegian diet has a significant carbon footprint. Norwegians eat a large amount of animal products and the dietary guidelines differ quite a lot from what people actually eat today," says Ph.D. student Julie Marie Lengle, who recently published her first article in Public Health Nutrition.

Lengle's has primarily worked on the part of the project focusing on the connection between our diet and climatic and environmental data. She emphasizes that a number of researchers have contributed to the article.

"In the study, we use the 2014 dietary guidelines, but their main points do not differ very much from the new guidelines that the Norwegian Directorate of Health will be publishing after the summer.

"The new guidelines will reduce the upper limit for the consumption of red meat, which will contribute to an even greater reduction in our diet's environmental footprint—that is, if the guidelines are followed. The international EAT Lancet Report goes still further and aims to reduce the carbon footprint even more.

"The report recommends a substantial reduction in the consumption of animal products compared to the Norwegian guidelines and the consumption of more carbohydrates from wholegrains. But such far-reaching changes in our diet can turn out to be unrealistic in a Norwegian context," says Lengle.

In earlier studies on the connection between diet and its impact on the climate, only greenhouse gas emissions were taken into account, whereas the NOR-Eden Project has a wider perspective: the study also examines the environmental impact of water and land use, acidification and eutrophication—the result of over-fertilization, which can lead to harmful algal blooms.

"It was surprising to discover that tea and coffee result in such a large carbon footprint here in Norway. I think many people believe that it doesn't matter if we throw away our coffee grains, but this is also a kind of food waste that we should try and reduce in the future," says Lengle.

She thinks it is exciting to work in a field that many people have an opinion on, but finds it rather frustrating to see all the opposition in social media when nutrition and dietary advice are being discussed.

The last part of the project, which we have only just begun to work on, will look at the public procurement of food and the effects that this can have.

"We will be studying how we can develop tools that can help public bodies to purchase healthy and sustainable food. It should be simpler to make the right choices. There is great potential in the field of public procurement because of the large quantities involved.

"We need overarching structural changes because measures on an individual level are not enough. We just hope the politicians will listen to what we have to say," concludes Andersen.