21 Feb Seafood as a sustainable alternative to meat?
With the growing attention on environmental sustainability, there has been a common narrative call to transition from meat to more plant-based foods. This transition is thought to have environmental benefits, although the complexity of this topic prevents simple conclusions. A caveat to this transition is reduced content of certain nutrients found in meat in plant-based foods. Instead of focusing solely on this so-called ‘green shift’, some researchers are suggesting that perhaps more effort should go towards a ‘blue shift’, by increasing the consumption of seafood over meat from land-based animals.
Researchers from the Research Institutes of Sweden and Dalhousie University gave 41 species of seafood a nutrient density score based on 24 nutrients related to dietary reference intakes or maximum recommended intakes. They found that when comparing nutrient density of seafood against their greenhouse gas (GHG) emissions, compared to land-based animals, seafood often came out on top. When compared to chicken, pork, and beef, approximately half of the seafood species had a higher ratio of nutrient density to GHG emissions.
Certain salmon species and small open-water fish such as herrings and anchovies had the best balance of nutrient density to GHG emissions. However, these species only make up a small portion of total seafood consumption due to either low production or low demand.
Interestingly, so-called ‘whitefish’ – which make up the greatest portion of seafood consumed around the world – had some of the lowest nutrient density scores and highest CO2 emissions of all species analysed.
Seafood contains many essential nutrients that are harder to come by in terrestrial animal-sourced foods, such as certain essential fatty acids, but they also scored well in this study’s metric due to low sodium and saturated fat content.
The researchers emphasised the future potential for seafood as both an environmentally sustainable food source, but also as a strong nutrient source. They stated that the main source of GHG emissions from capture fisheries is the burning of fuel and that there is potential for reducing these emissions by utilising low-emission technology in the future.
In this discussion, consideration must be taken of the environmental consequences beyond GHG emissions, such as biodiversity. The study also found significant variations in nutrient density between farmed and wild seafoods, even between very similar species. Expanding the current dataset to build a more comprehensive picture of seafood’s nutritional and environmental profile would achieve a more complete picture.
This SNippet was written by Jacob Knight, a summer student in the SNi team.