Blockchain technology is helping to meet sustainability challenges (see G. Chapron Nature 545, 403–405; 2017), for example in renewable energy (M. Andoni et al. Nature 548, 158; 2017) and conservation (Z. Baynham-Herd Nature 548, 523; 2017). Food security could also benefit from the technology's transparency, relatively low transaction costs and instantaneous application.

Blockchain assignment of unique digital identifiers to food products would make them traceable through supply chains, along with their growth conditions, batch numbers and expiry dates. This would help to prevent food waste, allow consumers to work out the ecological footprint of their food, and guide the distribution of surplus food to those who need it.

This shared and immutable register of foods and transactions would prevent fraud and enable source identification of food-borne illness. And as digital technologies are increasingly used to manage farms, blockchain will promote sharing of on-farm data.