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The US Department of Health and Human Services is encouraging Americans to eat more meat.

But meat-eating has well-documented adverse effects on human health, the environment, and animal welfare.

Researchers recently examined the effectiveness of dozens of interventions to reduce meat consumption.

The development of effective psychological nudges to reduce meat-eating over time remain elusive.

Robert F. Kennedy, the United States Secretary of Health and Human Services, is an unapologetic meat enthusiast—he claims that eating beef twice a day has enabled him to shed 20 pounds and has improved his mental clarity. Recently, he upset both the medical community and animal protectionists by elevating meat (and particularly red meat) to the top of the recommended healthy food pyramid.

Kennedy’s enthusiasm for increasing meat consumption runs counter to decades of nutrition research. Epidemiological studies, for example, have found that consumption of red meat is associated with increased risks of type II diabetes and cardiovascular disease. And according to the World Health Organization, eating the equivalent of just two slices of bacon a day increases your chances of colorectal cancer by nearly 20 percent.

To the presumed delight of RFK Jr. and to the dismay of animal activists and nutritionists, the meat trend line is going in the opposite direction. Americans are eating meat at near record levels, and worldwide meat consumption is doubling every 23 years.

Successful and Unsuccessful Health Campaigns

In her book Meathooked, the science journalist Marta Zaraska argues there are striking parallels between our “2.5 million-year obsession with meat” and forms of drug addiction. The comparison is sobering. For example, between 1975 and 2025, the percentage of Americans who smoked cigarettes dropped from nearly 40 percent to 10 percent. During the same period, meat consumption in the United States rose from 170 pounds per person in 1975 to 230 pounds per person.

Contrary to conventional wisdom, Gallup polls have found that the number of vegetarians and vegans in the United States has not budged—from 6 percent in 1990 to just 5 percent in 2023. In a 2014 survey of 12,000 American adults, researchers found that 85 percent of vegetarians and vegans eventually went back to eating meat. Yet in the United States, massive numbers of people who once smoked successfully quit. (I am one of them.) This pattern suggests that giving up meat may actually be harder than giving up cigarettes

American per capita meat consumption has increased 33 percent since Peter Singer published Animal Liberation, the 1975 book that jump-started the contemporary animal rights movement. The unavoidable fact is that campaigns to promote plant-based diets have largely failed.

Decades of Research on Reducing Meat Consumption

For two decades, researchers have studied the relative effectiveness of different approaches to motivate people to reduce their meat consumption. These techniques have included manipulations of restaurant menus, “Eat Less Meat" pledge challenges, changes in portion sizes, and exposure to gory animal-cruelty leaflets and videos.

Some pro-plant interventions can have immediate effects. In one study, researchers at the University of East Anglia placed images of cute food animals alongside meat-based items on menus at a university cafeteria for six days. Orders of meatless dishes were 22 percent higher in those days as compared to control periods with no animal photos on the menu. And, in an online experiment, Psychology Today blogger Sophie Attwood and her colleagues found that exposure to a pro-environment message significantly boosted their subjects' intentions to eat a hypothetical vegetarian meal.

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While these findings are encouraging, can meat-reduction interventions produce lasting changes in what people actually eat in real-world situations?

In a paper published in the journal Appetite, Stanford University’s Seth Green and his colleagues took this issue on. They used a statistical technique called meta-analysis to pool the results of 35 papers on the effectiveness of meat-reduction interventions. The papers described the results of 112 separate meat interventions with approximately 87,000 participants.

Crucially, the researchers only included studies with randomized control designs in which some subjects were exposed to a meat-reduction manipulation while others were randomly assigned to no-treatment control groups. The researchers also restricted their analysis to studies that actually measured changes in meat consumption at least one day after the intervention.

The Results: Effective Meat Reduction Is Elusive

To say the least, the results were disappointing. Collectively, the nudges barely moved the needle in reducing the consumption of meat and animal products. Over the 112 interventions, participants exposed to the interventions ate nearly as much meat as those in the control conditions. The effect sizes of the interventions were so small that, after receiving the meat-reduction messages, only 1 or 2 people out of 100 actually changed in their meat consumption. (For stat nerds, the standard mean difference between the intervention and the control groups was a meager 0.07.)

There was, however, a modest bright spot. Among studies that focused exclusively on red meat, some of the interventions proved more effective. While the effects were still small, about 10 people out of 100 in the red meat studies appeared to change. But, as researchers cautioned, these subjects may have substituted chicken or fish for red meat rather than reducing overall meat consumption.

Green and his colleagues correctly concluded, “These findings suggest that reducing meat and animal product consumption is an unsolved problem.” But their results point to a starker conclusion: that it is nearly impossible to motivate large numbers of people to reduce meat consumption through campaigns that rely on convincing them it is bad for their health, the environment, and for animals. Most people already know this—and yet they continue to eat meat.

Rather, meaningful meat‑reduction efforts may need to incorporate strategies similar to those that produced the remarkable success of the anti‑smoking movement. These included taxation and price increases on cigarettes, restrictions on where smoking was permitted, and bans on cigarette advertising.

These types of government regulations on meat are unlikely. But a technological solution may help wean people from eating real animals—the development of lab-grown meat made from animal cells. This "clean meat" is already available in a few places. But it will need to be both tastier and more reasonably priced to catch on widely. And it presently faces resistance from both vegetarians and carnivores. See Why Do People Think Cultured Meat is Disgusting?

Green, S. A., Smith, B., & Mathur, M. (2025). Meaningfully reducing consumption of meat and animal products is an unsolved problem: A meta-analysis. Appetite, 108233.

Isbanner, S., Fechner, D., & Attwood, S. (2025). Goal-framing theory and sustainable food choices: Leveraging spillover to activate moral goals. Appetite, 207, 107886.

Mathur, M. B., Robinson, T. N., Reichling, D. B., Gardner, C. D., Nadler, J., Bain, P. A., & Peacock, J. (2020). Reducing meat consumption by appealing to animal welfare: Protocol for a meta-analysis and theoretical review. Systematic reviews, 9(1), 3.

Murray, S., Meleady, R., & Hodson, G. (2026). Seeing animals, choosing plants: Evidence from a cafeteria field study on food choice. Journal of Environmental Psychology, 102988.

Zaraska, M. (2016). Meathooked: The history and science of our 2.5-million-year obsession with meat. Basic Books.

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