Plant content in packaged foods is related to lower emissions and better nutrition quality

Background

Food systems are a major contributor to global greenhouse gas emissions (GHGe). Dietary patterns that are high in animal-based foods and low in plant-based foods have contributed to rising GHGe. The lower GHGe of plant-based foods compared to animal-based foods highlights their potential role in more environmentally sustainable diets. Despite the growing role of packaged foods in diets, little is known about how their plant content relates to environmental and nutritional outcomes. This study aimed to investigate how the proportion of plant content in packaged foods relates to their GHGe and nutritional quality.

Methods

We conducted a cross-sectional analysis of 18,028 packaged foods obtained from the 2024 FoodSwitch database that includes information on packaged food and beverage products sold by five major Australian supermarket retailers. Plant content (g/100g), estimated GHGe (kg CO₂ eq/kg), and nutritional quality were evaluated. Nutritional quality was assessed using the Health Star Rating (HSR), Australia’s voluntary front-of-pack nutrition labelling system that rates products from 0.5 to 5 stars. Linear regression models were applied to examine associations between plant content and both GHGe and HSR, overall and by food category.

Results

Overall, a 10g increase in plant content was associated with a ∼10% reduction in GHGe (p < 0.001) and a 0.15-star increase in HSR (p < 0.001). The categories ‘Meat products’ and ‘Dairy’ had the highest GHGe and lowest plant content and exhibited the largest percentage reductions in GHGe as plant content increased.

Conclusions

Greater plant content in packaged foods was associated with lower GHGe and higher HSR scores, suggesting that plant content may serve as an indicator of both environmental sustainability and nutritional quality. Given current high levels of reliance on packaged foods, increasing plant content in these products may represent a potential method of improving both planetary and human health.

Key messages

• Higher plant content in packaged foods is associated with lower greenhouse gas emissions and improved nutritional quality, supporting its role as an indicator for more sustainable packaged foods.

• Plant content may serve as a practical metric to inform food labelling and policy strategies aiming to improve environmental sustainability and nutritional quality of packaged foods.