Shifting to Sustainable Diets: How Global Food Choices Impact Our Planet

A recent study led by UC Santa Barbara and international researchers unveils the environmental benefits of sustainable global diet shifts. The Indian diet emerges as the most beneficial, with substantial reductions in environmental pressures. 

A monumental shift in global diets towards sustainability could significantly combat climate change and global food insecurity. However, implementing such changes on a worldwide scale presents complex challenges. Researchers led by UC Santa Barbara’s National Center for Ecological Analysis & Synthesis (NCEAS) tackled this issue head-on to better understand the potential global impacts.

“Changes in food demand in one part of the world can have cascading environmental and human welfare implications for people around the world,” lead author Joe DeCesaro, a UC Santa Barbara graduate student in environmental data science, said in a news release.

In a pioneering study published in Environmental Research Letters, DeCesaro and an international team of researchers assessed the environmental pressures associated with global dietary shifts to four types of diets: Indian, Mediterranean, EAT-Lancet (largely plant-based) and average government-recommended food-based dietary guidelines (FBDGs).

They found that the Indian diet could potentially reduce global food production-based environmental pressures by 20.9%, while the FBDGs could increase these pressures by 35.2%.

The study highlights the critical role the global food system plays in environmental change, contributing to about a third of global greenhouse gas emissions and utilizing more than 70% of freshwater resources.

Transitioning towards sustainable diets — reducing resource-intensive foods like red meat and increasing nutrient-rich plant-based foods — could greatly alleviate environmental pressures.

NCEAS director and co-author Ben Halpern emphasized the importance of understanding the broader implications of such diet shifts.

“We wanted to know who would actually be feeling the change from the food production if these shifts occur,” he said in the news release.

By analyzing various factors, including dietary trends, trade flows and environmental pressures, the researchers mapped out the changes that could occur with each diet shift.

“Are poorer countries paying the environmental price of producing higher pressure foods that are being eaten by richer countries or vice versa?” DeCesaro added.

Their findings reveal that shifts to three of the four diets — excluding the FBDGs — led to reduced global cumulative environmental pressures. The Indian diet stood out due to its lack of red meat consumption, which is a significant factor in reducing environmental impacts.

Interestingly, the study also found that high-income countries would experience the most significant reductions in environmental pressures.

“Higher-income countries’ average current diets have higher consumption quantities of most food categories than the recommended quantities in our diet scenarios,” DeCesaro added.

Lower-income countries, however, might see an increase in food-production-related pressures due to meeting more of their nutritional needs.

To mitigate these pressures while ensuring food security and nutritional equity, the researchers recommend that wealthier nations offer support through access to efficiently produced imports, economic development and sharing of sustainable agricultural practices.

“Sharing sustainable agricultural practices will help reduce any increases in pressures seen from diet shifts,” DeCesaro added.

As the team progresses in their research, they aim to analyze current food trade patterns and the environmental pressures involved, without dietary changes.

Summarizing the broader implications, Halpern added, “A big message from our work is that the decisions we make about what we eat are important for reducing our environmental footprint, but other people may pay the price for those decisions.”

Understanding the ripple effects of our dietary choices is crucial for fostering a healthier planet. This study serves as a reminder of the power we hold in making impactful changes through our daily food consumption decisions.