How a month of abstinence can lead to 'meat disgust'

There are some surprising impacts of cutting out meat, even for a short period, which can carry on well beyond the end of abstinence.

It is widely understood that livestock have a heavy impact on the climate and research indicates that switching to a plant-based diet is one of the most impactful steps individuals can take to reduce their carbon emissions from food. Animal products are responsible for 57% of global food-related emissions, compared with plant-based foods which contribute 29% of the total – even though animals provide less than one fifth of the world's total energy from food.

Every year in January, millions of people worldwide choose to start the year by giving up animal products for the month. Others may choose starting the week with each Monday as a meat-free day, or take part in the no-meat-in-the-daytime initiative Vegan Before 6. Besides these initiatives, there are plenty of year-round efforts to reduce meat intake. The "less but better" concept involves eating less meat but ensuring it is more ethically produced. "Reducetarianism", meanwhile, involves people simply reducing their meat, dairy and egg intake.

People have many different reasons for reducing their meat consumption, whether for animal welfare, climate or dietary reasons. Regardless of their motivations, a recent study found that low meat diets can be beneficial across a range of environmental reasons, with vegan diets having lower greenhouse gas emissions, lower water use and lower impacts on biodiversity.

For those making the switch for only a short period, however, those impacts may initially only be lowered during that time. But there are indications that there could also be some surprising lasting impacts that can go well beyond January, Monday, or whichever time period someone might choose to avoid or cut down on animal products.

One of the most well-known campaigns to reduce animal product intake is Veganuary, which encourages people to eat vegan food for the month of January. In 2024, around 25 million people worldwide joined the campaign, according to Veganuary's statistics.

The campaign claims that the effects of a month free of animal products can extend beyond January, resulting in longer-term dietary changes. According to its own survey, the Veganuary campaign claims that 81% of participants said they had maintained a significant reduction in meat consumption six months after taking part.

There are many reasons why these effects could continue beyond the month. Early research has linked participation with increased experience of "meat disgust". A small independent study of 40 participants who normally ate meat found that those who reduced their meat intake in January were more likely to have feelings of disgust towards meat once the month had ended (even though many had lapses). Of the 40 participants, 28 reported an increase in meat disgust.

"The more meat people managed to cut out during Veganuary, the more their meat disgust grew over that month," says study author Elisa Becker, a postdoctoral researcher at the University of Oxford in the UK. "When you stop eating meat, that disgust ramps up, which is really interesting. "This suggests that just one month of meat abstinence changes how you view meat."

Becker has also found a connection between increased meat disgust and reduced meat consumption in a larger six-month study carried out at the University of Exeter in the UK, finding 74% of vegetarians were classified as "meat disgusted".

"Both studies show a connection between meat intake and meat disgust – the less meat you eat, the more disgusted by meat you tend to become," Becker says.

The study didn't examine the reasons why participants chose to give up meat, so it is possible they could have already had some concerns that contributed to preexisting feelings of disgust.

Becker's findings have, however, been confirmed and expanded by Sophie Hearn and Natalia Lawrence at the University of Exeter in unpublished research recently presented at a conference and seen by the BBC.

"This is an emerging area of social science research which seems to be revealing something quite interesting and important in terms of the consequences for meat consumption of the 'practice' or actual experience of cutting back or cutting out meat from your diet, for example by participating in Veganuary," says Carol Morris, principal research fellow at the Faculty of Social Sciences at the University of Nottingham in the UK, who has studied less-meat initiatives. "If you engage in meat reduction or elimination for a period it does seem to change your relationship with that foodstuff."

The research field is still in its early stages, but Morris suggests the phenomenon is worth further investigation.

"This could be some preliminary evidence suggesting that abstention from meat can strengthen disgust towards it," says Jared Piazza, a senior lecturer in psychology at Lancaster University in the UK who moral decision making as it relates to society, animals, and food.

"Ultimately, the relationship between meat abstention and disgust is likely a feedback loop. Avoiding meat over time can re-calibrate your appetite towards meat," says Piazza."However, research suggests that in the short term, meat eaters who attempt to abstain from meat within a month-long pledge experience greater cravings for meat than meat eaters who don’t abstain. Thus, one shouldn’t expect abstention to lead to meat disgust immediately. It takes a little time."

In 2023, a team led by Peter Scarborough, professor of population health at the University of Oxford, released a study on the environmental impacts of different diets, which included a large number of vegans and vegetarians from a dataset of 55,000 people in the UK. This real-world data was crucial, Scarborough says. "Quite often researchers just model what a vegan and vegetarian diet might be and make some kind of crazy assumptions, like saying: 'Oh, well, I'm sure vegans eat just the same as meat eaters, but instead of sausages, they eat broccoli.'"

The analysis was the first to review the impact of diets on a range of environmental measures beyond carbon emissions, including land use, water use, water pollution and loss of species.

The research concluded that the vegan diet had the lowest carbon emissions – just 25% of the greenhouse gas emissions of a diet that includes more than 100g of meat per day. Plant-based diets' lower emissions still held even when air miles and the resources taken to grow crops were taken into account. The most carbon-intensive vegan diet still had only 37% of the greenhouse gas emissions of the diet consisting of more than 100g of meat per day. (Read more about the environmental impact of vegan and vegetarian diets here).

For those who don't follow a vegan or vegetarian diet, simply eating less meat had a substantial impact on emissions, Scarborough found. On a population level, these reductions are significant. If big meat-eaters in the UK were to cut some of it out of their diet, it would be equivalent to taking eight million cars off the road, according to Scarborough.

In 2024, researchers in Scotland found that across the UK, the change that made the biggest difference to total meat consumption was reducing meat portion size. The next most impactful measure was fewer meat-eating days, fewer meat consumers (this includes vegans, vegetarians, flexitarians and people who eat meat sparingly) and finally fewer meat-containing meals (for example, including a vegetarian lunch). 

Reducing portion size, the researchers say, could be the most impactful action for "meat-oriented consumers", who would be unlikely to forego meat entirely for a day each week, or month each year.

Besides reducing portions, the type of meat and animal products eaten make a difference too. Certain types are lower-carbon than others. Beef has the highest carbon footprint, followed by lamb, as both come from ruminant animals that belch out potent methane when they digest their food. Meat from small, non-ruminant animals, such as chicken, turkey and duck has a much lower carbon footprint. (Read more about which protein-rich foods can help us curb our emissions).

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Scarborough and his colleagues hope their findings will be used to inform public policy. However, he says there is a lack of political appetite inthe UK to introduce meat-reduction policies, which countries such as Denmark have done. Becker agrees there is little public support for meat reduction policies. The meat paradox – the fact that most people oppose animal mistreatment but still want to eat factory-farmed meat – means that people tend to rationalise their meat consumption and defend it quite vigorously, she says.

"Let's be pragmatic about this," says Morris. "For everyone to become plant-based is probably not realistic." And while by far the most impactful dietary change remains to eat a plant-based diet, Morris welcomes other initiatives, from "less but better", to cutting out animal products for a time, if these help people reduce their impact on the planet.

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