Dietary change looks likely to be the most significant factor in increasing land requirements to feed a growing population in many regions of the world. In a paper published in early 2012, researchers from Austria and the Netherlands analysed changes in land requirements from 1961 to 2007 in order to determine the most significant drivers of changes in land use for food production and how they differ between global regions.
Overall increases in output per unit of land in the past were predominantly due to population growth and dietary change. The relationship between population change and dietary diversification was found to be inverse i.e. as a rule of thumb diets become more varied as populations decrease (most likely a symptom of globalization and demographic transition). Trends in increased meat and dairy production and intake have been well documented. A 2010 paper, authored by Tara Garnett, stated the importance of moderating our consumption of meat and dairy products because the livestock sector is responsible for a substantial proportion of greenhouse gas emissions and because technological climate change mitigation activities can only go so far. When land use change and agriculture are combined their contribution to global greenhouse gas emissions is around 30%.
The 2012 paper concluded that dietary change is predicted to be more significant a factor in increasing land requirements for agriculture than population growth in the near future with developed countries and emerging economies the biggest drivers of this trend.