Milk has come out substantially higher than other beverages in an analysis that pits impact on climate against nutrient density.
The food chain is major contributor to greenhouse gas (GHG) emissions, and suggested strategies for curbing emissions have included switching from more animal-based to plant-based foods as red meat and dairy production are amongst the highest contributors.
But a team of researchers from Uppsala in Sweden and Seattle in the US say the nutritional dimensions of changing consumption patterns to lower GHG emissions “remain relatively unexplored”.
In what is billed as the first study to look at nutrient profile in relation to emissions throughout a product’s lifecycle, the researchers used an index called the Nutrient Density to Climate Impact (NDCI) index. Nutrient density was worked out using the Nordic Nutrition Recommendations for 21 nutrients.
The NDCI was worked out for bottled carbonated water, soy drink, milk, soft drink, orange juice, beer, red wine, oat drink.
The carbonated water, soft drink and beer all scored zero due to their low nutritional value, while the red wine and the oat drink scored below 0.1.
Orange juice and soy drink scored 0.25 and 0.28 respectively.
The NDCI was the milk, however, was considerably higher, at 0.54.
“Future discussions on how changes in food consumption patterns might help avert climate change need to take both GHG emission and nutrient density of foods and beverages into account,” concluded the researchers in Food & Nutrition Research journal.
They recommended that the index be used to explore different dietary settings, and as nutrition and climate research advance more complete data will become available – and more sophisticated lifecycle analyses can be undertaken.
“In particular, GHG emissions of fortified drinks will probably be available, enabling comparisons in the future between more nutrient dense beverages,” they wrote.
Food and Nutrition Research 2010, 54: 5170
Nutrient density of beverages in relation to climate impact
Authors: Smedman, A, Lindmark-Mansson, H, Dreqnowski, A, Modin Edman, A-K