Men generally have bigger feet than women – and a bigger carbon footprint too, according to new research.

A joint UK-French study, at the LSE’s Grantham Research Institute on Climate Change and the Environment, found that men cause 26% more planet-warming gas emissions than women do, mainly because of the cars they drive and the meat they eat.

The researchers analysed French survey data on food consumption and transport patterns – the two factors that, together, account for 50% of the carbon footprint of French households. They found that, for men, the average annual carbon footprint associated with food and transport was 5.3 tonnes of carbon-dioxide equivalent; for women, it was 3.9.

The difference between the sexes is mainly accounted for by men’s higher consumption of red meat and greater use of cars – both “often associated with male identity”, concluded the study authors in an LSE press release. “Our results suggest that traditional gender norms, particularly those linking masculinity with red-meat consumption and car use, play a significant role in shaping individual carbon footprints,” said study co-author Ondine Berland, a LSE fellow in environmental economics.

‘Striking’ gender gap

“Research into gender gaps is often plagued by difficult decisions about which factors to control for,” said The Guardian. Men need more calories than women, for example, but “they also eat disproportionately more than women”. Men also tend to drive longer distances when commuting, and they also generally have higher incomes, which are themselves “correlated with higher emissions”.

But, even after the study authors controlled for socioeconomic factors such as income, job type, household size and education, the emissions gap between men and women was still a significant 18%.

It is “quite striking that the difference in carbon footprint in food and transport use” between French men and women is “around the same as we estimate” globally for high-income people compared to lower-income people, study co-author Marion Leroutier, an assistant professor at Crest-Ensae Paris, told the paper.

Higher personal costs

The carbon-footprint gap the study identifies could help explain “the growing climate concern gap between men and women”, said The Independent. It’s possible that men are less inclined to support climate action because there are “higher personal costs” for them in doing so, such as giving up red meat and reducing car use.

Alternatively, it could be that women’s lower-carbon lifestyles “might reflect and reinforce deeper values and priorities”: their carbon footprints are smaller because they’re more concerned about the climate.

Either way, it’s clear that “public messaging and policy design” on lowering emissions needs “to take social norms and gender roles into account, not just market signals or price incentives”. Strategists wanting to target “high-emission activities like driving and eating meat” need to factor in that this will “disproportionately affect men, especially those who associate consumption with identity or status”.

And the rewards of successful messaging could be impressive. If all adult men adopted the average food and transport “carbon intensity of women”, say the study authors, France’s emissions from food and transport would fall by more than 13 million tonnes of carbon-dioxide equivalent a year. That’s about triple the emissions decrease that France is targeting across those sectors, to comply with its 2030 climate targets.