Ecological Footprint accounting quantifies the supply and demand of Earth’s biocapacity. The National Footprint Accounts (NFA) are the most widely used Ecological Footprint (EF) dataset, and provide results for most countries and the world from 1961 to 2014, based primarily on publicly available UN datasets. Here, we review the evolution of the NFA, describe and quantify the effects of improvements that have been implemented into the accounts since the 2012 edition, and review the latest global trends. Comparing results over six editions of NFAs, we find that time-series trends in world results remain stable, and that the world Ecological Footprint for the latest common year (2008) has increased six percent after four major accounting improvements and more than thirty minor improvements. The latest results from the NFA 2018 Edition for the year 2014 indicate that humanity’s Ecological Footprint is 1.7 Earths, and that global ecological overshoot continues to grow. While improved management practices and increased agricultural yields have assisted in a steady increase of Earth’s biocapacity since 1961, humanity’s Ecological Footprint continues to increase at a faster pace than global biocapacity, particularly in Asia, where the total and per capita Ecological Footprint are increasing faster than all other regions.

Fish and seafood are central to the Portuguese diet, comprising a significant portion of Portugal’s Ecological Footprint. Diversifying dietary preferences is important because it has the potential to reduce pressure on marine ecosystems. We explored this opportunity by coupling (1) an Ecological Footprint assessment of Portugal to quantify the environmental impacts of Portugal’s food consumption choices (particularly fish and seafood), with (2) a consumer survey to assess attitudes towards fish and seafood of Portuguese residents and their willingness to modify their preferences, thus shedding light on the potential for sustainable dietary choices in Portugal and the best strategies by which to achieve them. Ecological Footprint results confirm that Portugal is unique in the Mediterranean region in that its food Footprint is driven by fish and seafood consumption, while, for most other countries, the main driver is meat. Results from the consumer survey show that Portuguese fish and seafood preferences are characterized by a high frequency of consumption and a preference for high trophic level species. Age was the primary demographic factor influencing consumption habits in Portugal. Moreover, Portuguese consumers lack knowledge on sustainable fishing practices. Actions and strategies to increase sustainable dietary choices in Portugal will need to consider these factors. We recommend targeted outreach messaging for different age groups, more and better information on sustainable options, together with efforts to protect marine biodiversity. Future research needs to better understand the whole value chain and all relevant stakeholders of the fish and seafood sector for more effective incentives for Footprint reduction.