Dietary Guidelines Incompatible With Global Climate Change Targets

A team of researchers, including some with the University of Adelaide in Australia, has found most dietary recommendations provided by national governments are incompatible with global health and environmental targets such as the Paris Climate Agreement, and are in need of reform.

In the study, published in The BMJ, University of Adelaide Health and Medical Science Honours student Luke Spajic worked alongside researchers from the livestock, environment, and people program at the University of Oxford in the United Kingdom, and Harvard and Tufts Universities in the United States.

The researchers extracted the recommendations from the dietary guidelines of 85 countries including Australia. They modeled the recommendations against global health and environmental targets, including the goal to reduce premature mortality from noncommunicable diseases by one-third and the agreement to limit global warming to less than 2° C.

For comparison, the impacts of adopting the World Health Organization global dietary recommendations, and the more comprehensive and ambitious recommendations of the EAT-Lancet Commission on Healthy Diets from Sustainable Food Systems, also were examined.

Spajic says they found that, on average, adoption of national dietary guidelines was associated with a 15% reduction of premature mortality and a 13% reduction in greenhouse gas emissions.

“However, a third of guidelines were incompatible with the global health agenda on noncommunicable diseases, and between 67% to 87% were incompatible with the Paris Climate Agreement and other environmental targets,” Spajic says.

“Taken together, 98% of national guidelines were incompatible with at least one global health and environmental target, meaning that even if the whole world followed them, we would still fail to meet the targets governments have signed up to.”

Spajic says he wasn’t all that surprised by these findings, as many national dietary guidelines in the study hadn’t been updated for some time and didn’t include recommendations around environmental sustainability.

“In Australia, our dietary guidelines were last published in 2013, and absent from those are recommendations that factor in environmental sustainability,” Spajic says.

Adoption of the World Health Organization recommendations was associated with similar health and environmental changes as many national guidelines. However, adoption of those of the EAT-Lancet Commission on Healthy Diets from Sustainable Food Systems was associated with a one-third greater reduction in premature mortality, more than three times greater reductions in greenhouse gas emissions, and general attainment of the global health and environmental targets.

In Australia, adoption of the EAT-Lancet Commission on Healthy Diets from Sustainable Food Systems could lead to a reduction in greenhouse gas emissions of 86% and a reduction in premature deaths of 31,000 (compared with 61% and 29,000, respectively).

Spajic says Australia’s national guidelines could be both more healthful and more sustainable.

“We urgently need to update our national dietary guidelines to reflect the latest evidence on healthy eating,” Spajic says. “The impact of recent drought and bushfires in Australia also has added to the argument for environmentally sustainable recommendations to be included in our national guidelines.

“In Australia, we found that placing stricter limits on red meat and dairy would provide the greatest environmental benefit, and increased recommendations of whole grains, nuts, and seeds, as well as further limits on processed and red meat would have the biggest impact on health,” he says.

Marco Springmann, PhD, from the Nuffield Department of Population Health at the University of Oxford, who led the study, says more ambitious guidelines on red meat and dairy would be a good starting point, but the guidelines aren’t a solution in themselves.

In the study, less than one-half of all countries with national food-based dietary guidelines fulfilled any of their recommendations, and no country simultaneously fulfilled all recommendations.

“Food policies also need to encourage us to eat closer to national guidelines, and this includes investment in targeted public health campaigns that communicate what healthy and sustainable eating looks like,” Springmann says.

The study also highlights the need for national food guidelines to be reviewed more frequently and compared with global health and environmental targets.

— Source: University of Adelaide