Rethinking insects as alternative protein

The report argues that commercial insect farming in high-income, temperate regions often fails to meet its theoretical sustainability promises. While insects have lower greenhouse gas emissions than beef, they often perform worse than the soymeal and fishmeal they are intended to replace. The authors identify seven key challenges: outdated life cycle assessments, under-utilization of organic waste as feed, limited substitution of meat in human diets, the reinforcement of industrial animal agriculture through use as feed, biodiversity risks from unintentional releases, emerging animal welfare concerns, and the opportunity cost of diverting investment from more promising plant-based or cultivated proteins.

• Greenhouse gas emissions for farmed insects in temperate climates range from 3 to 35.5 kgCO2eq per kg of protein, with a median of approximately 13.5 kgCO2eq/kg protein. While these figures are lower than beef (75–170 kgCO2eq/kg), they approach the ranges for chicken (18–36) and pork (21–53), and are generally higher than the soymeal (0.9–2.2) and fishmeal (0.2–9.3) they typically displace.
• Insect farming offers a structural land-use advantage over conventional land animals, with direct land use ranging from 0 to 18 m² per kg of protein under favorable conditions. However, this efficiency drops sharply to up to 67 m² when insects are fed food suitable for human consumption.
• The theoretical benefit of using organic waste as feed is rarely realized in commercial practice due to variability in waste composition, regulatory hurdles, and competition with other sectors like bioenergy production. An assessment of 13 farms in the US and Europe found that none used food waste as feed, relying instead on high-quality grain-based substrates.
• In Western markets, insect-derived products rarely replace carbon-intensive meats; they are instead used in snacks, pasta, and bread, often replacing low-impact plant-based ingredients. The largest market for farmed insects is currently pet food, which accounts for approximately half of the total market.
• A significant portion of farmed insects serves as an input for conventional animal agriculture and aquaculture, which may reinforce rather than disrupt high-impact industrial production. In the UK, insect meal's climate change impact (12.9–30.1 kgCO2 eq/kg protein) was found to be 5.7 to 13.5 times higher than soymeal.
• Insect farming poses ecological risks through the unintentional release of native or non-native species, which could out-compete pollinators, spread diseases, or harm crops. Many farmed species are non-native to the regions where they are produced, increasing the risk of biological invasions.
• There are emerging animal welfare concerns as scientific evidence suggests some insect species may be sentient and capable of suffering. Current industrial practices—including high-density housing, starvation before slaughter, and various killing methods—may pose significant welfare risks.
• Prioritizing insect farming may create opportunity costs by diverting funding and policy attention away from other alternative proteins, such as plant-based, fermentation-derived, and cultivated proteins, which may offer clearer long-term sustainability benefits.

APA

Verkuijl, C., Garzón, C., Shawoo, Z., Scherer, L., & Le Goff, G. (2026). Rethinking insects as alternative protein. Stockholm Environment Institute. https://www.sei.org/wp-content/uploads/2026/05/rethinking-insect-farming.pdf

Chicago

Verkuijl, Cleo, Camilo Garzón, Zoha Shawoo, Laura Scherer, and Gladys Le Goff. Rethinking insects as alternative protein. Stockholm Environment Institute, 2026. https://www.sei.org/wp-content/uploads/2026/05/rethinking-insect-farming.pdf.

Wikipedia

{{cite report |last1=Verkuijl |first1=Cleo |last2=Garzón |first2=Camilo |last3=Shawoo |first3=Zoha |last4=Scherer |first4=Laura |last5=Le Goff |first5=Gladys |title=Rethinking insects as alternative protein |publisher=Stockholm Environment Institute |date=May 2026 |url=https://www.sei.org/wp-content/uploads/2026/05/rethinking-insect-farming.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{verkuijl2026rethinking, author = {Verkuijl, Cleo and Garzón, Camilo and Shawoo, Zoha and Scherer, Laura and Le Goff, Gladys}, title = {{Rethinking insects as alternative protein}}, institution = {Stockholm Environment Institute}, year = {2026}, month = may, url = {https://www.sei.org/wp-content/uploads/2026/05/rethinking-insect-farming.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }