TL;DR: I've analysed temporarily subsidising plant-based meal kits as an animal welfare intervention. My preliminary estimate is that this averts 19 SADs/$ (90% CI: 5-49 SADs/$). I'm now looking for feedback and criticism, and suggestions on if/how to take this forward. Full doc is here. Cost-Effectiveness calculation is here.

Meta notes: The doc/spreadsheet/post took ~15hrs of effort. I wrote the doc and did the calculation. Claude did red-teaming and wrote ~all of this post (using the doc).

The Core Idea

If people experience a month of convenient, tasty plant-based dinners, some will continue reducing meat consumption afterward. We could pay for people to receive plant-based meal kits for ~1 month. This model would remove a lot of the initial friction associated with diet change. Then, we track whether this reduces their long-term meat consumption or catalyses dietary change. 

Why It Might Work (TOCs)

1. Individual diet change (most measurable): Participants reduce meat consumption long-term → Decreased demand for animal products → Fewer animals raised in factory farms
2. Social spillover effects (harder to measure): Participants share positive experiences → Shift in social norms around plant-based eating → Broader dietary change
3. Market effects (speculative): Increased demand for quality vegan meal kits → Companies invest in better products → Plant-based options become more accessible and normalised

Practical Implementation

The intervention

1. Provide participants with ~30 days of plant-based meal kits for free (negotiating bulk discounts from retailers).
2. Two variants to test:
   • One meal: Participants replace only their main meal (easier compliance, more likely completion)
   • Fully vegan: Participants are expected to eat a fully plant-based diet (potentially more transformative, harder to sustain)
3. Provide some post-intervention support: meal planning apps (eg. Cherrypick), or a grocery stipend during transition
4. Track outcomes through surveys/interviews at exit, 6 months, and beyond.

Ideal target demographic

• Know someone vegan/vegetarian (social proof/accountability)
• Already somewhat open to reducing meat consumption
• Eat meat 3-6 days/week (showing flexibility but room for impact)
• Socially connected (to maximise spillover effects)

Recruitment

• Referrals from existing vegans/vegetarians (key method)
• Advertising at relevant events
• Online outreach

Cost-Effectiveness Estimates

The headline number is 19 SADs/$ (90% CI: 5-49 SADs/$). This is broken down into three different scenarios. All estimates include spillover effects.

Details are here.

For comparison, the top potential interventions in AIM's 2025 and 2026 reports, are estimated at cost-effectivenesses of 153, 3-51, ~36-104, and ~30 SADs/$, respectively. 

Key Uncertainties

• Intervention length (shorter is cheaper but may reduce long-term impact)
• Discount negotiations with meal kit companies
• Long-term dietary change rates (currently assumed based on similar studies from Faunalytics)
• Whether "meat disgust" develops and matters for persistence
• Spillover effect magnitude

Model Simplifications

• Excludes overhead (staff time, coordination, survey costs, dropouts)
• Treats all meals as equal in SADs (likely wrong—dinner probably matters most)
• Uses Vasco Grilo's SADs/person-year estimates

Critical Assumptions

Core Assumption

• One month of eating plant-based dinners causes sustained reduction in meat consumption.
  • This isn't immediately clear. Habit formation alone may not be sufficient without accompanying belief/value shifts.

Practical Assumptions

• Meal kits are high-quality and easy to use (so people actually complete the trial)
• Can negotiate extended discounts with retailers (40-50% off is standard for first 2 weeks, aim to match that for a month)
• Can effectively account for social desirability bias in surveys
• Target demographic won't be saturated quickly

Why This Might Be Better Than the Numbers Suggest

1. Quality control: Unlike asking people to "go vegan," this provides instructions and ingredients, reducing risk of nutritionally inadequate or unpalatable attempts that create negative associations.
2. Higher compliance: Free food is a strong incentive! People are much more likely to actually try this vs. a purely motivation-based intervention.
3. Measurable: Can confirm delivery and track consumption more reliably than self-directed diet change.
4. Potential for higher conversion: If spillover effects are real and substantial, impact could be much larger than individual diet change alone.

Why This Might Be Worse Than the Numbers Suggest

1. Scaling challenges: May only work cost-effectively for specific demographics. At scale, people might claim interest just for free food.
2. Measurement problems: Surveys suffer from desirability bias. Actual long-term behaviour change could be much lower than reported.
3. Rebound effects: Once meal kits stop, friction returns. People might revert entirely or even overcorrect (eating more meat after feeling deprived).
4. Negative spillover: Bad experiences could make participants less likely to try plant-based eating in the future.

Please Give Feedback!

I'd really appreciate feedback from anyone on this. Here's some questions that I think anyone could weigh in on:

• Is this an appealing intervention? Would you participate?
• Which numbers in the cost-effectiveness model seem too high or too low?
  • You can copy the model and try your own numbers if you want!
• Am I missing anything really important in the model?
• Am I missing any good improvements in the intervention design?

You can leave a comment below, or comment directly on the doc or spreadsheet.

Potential Next Steps

I'm pretty uncertain what (if anything) to do next. I'd appreciate thoughts, especially from those with relevant background. Some options I've considered:

• Do more investigation.
  • Theoretical, eg. refining the plan.
  • Practical, eg. contacting meal-kit companies.
• Try and run a pilot, and apply for funding to do so.
  • I expect a decent pilot needs n=20-30 and would cost ~£4-6K.
  • I don't know who (if anyone) would fund this.
• Drop it, and focus on something different and more effective.