Men's meaty diets 'lead to 40% more carbon emissions than women'

Men's meal choices are bad for the planet, a study has shown – resulting in carbon emissions that are 41% higher than women's diets.

The difference is mainly down to meat intake, researchers found.

Emissions associated with non-vegetarian diets were 59% higher than those for vegetarian diets, they said.

People who chose healthier diets also had lower emissions, while those whose intake of saturated fats, carbohydrates, and sodium met WHO-recommended levels had lower emissions than people who exceeded the levels.

The researchers wrote: "We all want to do our bit to help save the planet. Working out how to modify our diets is one way we can do that.

"There are broad-brush concepts like reducing our meat intake, particularly red meat, but our work also shows that big gains can be made from small changes, like cutting out sweets, or potentially just by switching brands."

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Researchers led by Dr Holly Rippin, of the University of Leeds, analysed the diets of 212 people using published research in order to assign greenhouse gas emissions to more than 3,233 specific food items listed in the UK Composition Of Foods Integrated Dataset (COFID).

COFID already contains nutrition data and is commonly used to evaluate the nutrition of an individual's diets.

The researchers used this data to evaluate the diets of 212 adults who reported all the foods they ate within three 24-hour periods.

Food production is a major source of greenhouse gas emissions, accounting for about one third of emissions worldwide.

Previous research suggested that environmentally sustainable diets were often also less processed, less energy-dense, and more nutritious.

But much of that work has been conducted using measurements of sustainability for broad categories of food instead of specific food items, leaving room for greater accuracy in evaluating the environmental impact of individual diets.

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People must switch from meat-heavy Western diets to vegetarian or vegan diets to avert climate change, a UN-backed report warned last year.

By 2050, the world will need to produce 56% more food than in 2010, to feed a predicted 9.8 billion people.

If the level of meat and dairy consumption rises in line with current trends, 2.3 million square miles of forest will need to be converted for agriculture.

Our system of producing food already accounts for between 25-30% of greenhouse gases, the Creating a Sustainable Food Future report warned.

If the world requires millions of extra square miles for food production, it will clash with planned schemes to limit global warming, including so-called bioenergy with carbon capture and storage, or BECCS, schemes.

Limiting global warming to 1.5C would require 2.9 square million miles devoted to BECCS schemes, scientists warned.

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