Climate change further threatens food security through its impact on global food production and consequently on food prices. With growing populations and higher demand for food, the impact of climate change could result in an increase of 20% of people at risk of chronic hunger.

Diets link environmental and human health. Rising incomes and urbanization are driving a global dietary transition in which traditional diets are replaced by diets higher in refined sugars, refined fats, oils and meats. By 2050 these dietary trends, if unchecked, would be a major contributor to an estimated 80% increase in global agricultural greenhouse gas emissions from food production and to global land clearing. Moreover, these dietary shifts are greatly increasing the incidence of type II diabetes, coronary heart disease and other chronic non-communicable diseases that lower global life expectancies. 

If widely adopted, alternative diets that offer substantial health benefits could reduce global agricultural greenhouse gas emissions, reduce species extinctions, and help prevent diet-related diseases. The implementation of dietary solutions to the tightly linked diet–environment–health trilemma is a global challenge of great environmental and public health importance.

A typical meat-eater’s diet is responsible for almost twice as much global warming as vegetarian’s and almost triple that of a vegan. The Oxford University study suggested that cutting your meat intake in half could cut your carbon footprint by more than 35%.

There is no clear evidence that livestock grazing can significantly enhance soil carbon stores. And there is significant research that demonstrates greater carbon storage with no grazing.  Livestock grazing appears to be a questionable strategy for reducing global atmospheric carbon. Climatic conditions year to year, for instance, can shift carbon storage in grazed areas from a positive to a negative. Furthermore, any storage is gradual and takes years to accumulate, while carbon uptake by soils is finite and slows over time. And compared to almost all other ecosystems, arid rangelands are among the least productive ecosystems—hence have little potential for soil carbon storage compared to other ecosystems like forests.

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One cannot look at the soil carbon storage issue out of context. Livestock are among the greatest source of GHG emissions now—and reducing livestock numbers is the quickest and perhaps the most effective means of significantly altering GHG emissions. Furthermore, there are a host of collateral damages created by livestock production, from the destruction of soil biocrusts, killing of predators, water pollution, clearing of forests for pasture, and so on.

United Nations report 2010: A global shift towards a vegan diet is vital to save the world from hunger, fuel poverty, and the worst impacts of climate change.

Impacts from agriculture are expected to increase substantially due to population growth increasing consumption of animal products. Unlike fossil fuels, it is difficult to look for alternatives: people have to eat. A substantial reduction of impacts would only be possible with a substantial worldwide diet change, away from animal products.

It was estimated that changes towards more plant-based diets in line with the WHO’s global dietary guidelines could reduce global mortality by 6-10%. Food-related greenhouse gas emissions would be cut by more than two thirds.