This post summarizes a new meta-analysis from the Humane and Sustainable Food Lab. We analyze the most rigorous randomized controlled trials (RCTs) that aim to reduce consumption of meat and animal products (MAP). We conclude that no theoretical approach, delivery mechanism, or persuasive message should be considered a well-validated means of reducing MAP consumption. By contrast, reducing consumption of red and processed meat (RPM) appears to be an easier target. However, if RPM reductions lead to more consumption of chicken and fish, this is likely bad for animal welfare and doesn’t ameliorate zoonotic outbreak or land and water pollution. We also find that many promising approaches await rigorous evaluation.
This post updates a post from a year ago. We first summarize the current paper, and then describe how the project and its findings have evolved.
What is a rigorous RCT?
We operationalize “rigorous RCT” as any study that:
* Randomly assigns participants to a treatment and control group
* Measures consumption directly -- rather than (or in addition to) attitudes, intentions, or hypothetical choices -- at least a single day after treatment begins
* Has at least 25 subjects in both treatment and control, or, in the case of cluster-assigned studies (e.g. university classes that all attend a lecture together or not), at least 10 clusters in total.
Additionally, studies needed to intend to reduce MAP consumption, rather than (e.g.) encouraging people to switch from beef to chicken, and be publicly available by December 2023.
We found 35 papers, comprising 41 studies and 112 interventions, that met these criteria. 18 of 35 papers have been published since 2020.
The main theoretical approaches:
Broadly speaking, studies used Persuasion, Choice Architecture, Psychology, and a combination of Persuasion and Psychology to try to change eating behavior.
Persuasion studies typically provide arguments about animal welfare, health, and environmental welfare reason
From the comments of the post:
I would give him feedback, but frankly I find his proposal too confusing to critique. I've read it twice over three days now. At first, I thought he was referring to social institutions, especially because he used an example about driving. Then he claimed businesses are willing to do late-stage innovation and charities should fill in the gap.
What does he want innovated? Private institutions like charities and businesses, or public institutions?
If he had given any references to this allegedly thriving literature or any concrete examples of how one idea could go from academic to charity to business, that would have been more helpful. If he's just talking about people trying out academic ideas in, say, schools, we already do that, so that's not a very exciting argument for me.
I agree with Robin that this is a criminally neglected cause areas. Especially for people who put strong probability on AGI, Bioweapons, and other technological risks, more research into institutions that can make better decisions and outcompete our current institutions seems to be important.