“Average weekly unit sales of plant-based products increased significantly (57 %) during the intervention period (incidence rate ratio (IRR) 1·52 (95 % CI1·51, 1·55)). Plant-based product sales decreased post-intervention but remained 15 % higher than pre-intervention (IRR 1·13 (95 % CI 1·12, 1·14)). There was no significant change in meat sales according to time period. The increase in plant-based product sales was greatest at superstores (58 %), especially those located in below average affluence areas (64 %).”
From the main body of the text: “Plant-based products represented 0·011 % of product unit sales in the pre-intervention period. This increased to 0·016 % during the intervention period and 0·012 % in the post-intervention period. Meat products represented 26·52 % of sales in the pre-intervention period, 26·51 % during the intervention period and 26·32 % in the post-intervention period. The remainder of sales were represented by non-meat products (73·47 % in pre-intervention and intervention periods, 73·67 % in the post-intervention period).”
One thing to flag on reading into this as evidence against plant-based sales leading to lower meat consumption is how much harder it will be to detect a significant effect on meat consumption. The background variation on those is much higher so to detect a significant effect from a campaign like Veganuary we would need a much larger total effect size. Even if the 0.05% of pre/post change in plant-based came 100% from meat I’d expect it still would not be significant.
Agreed, though if their model isn’t correctly specified to identify the causal effect on meat (which I agree is tough here), then presumably the effects on plant-based sales would also be suspect.
That is disappointing... However, there’s still at least some benefit from increased plant-based product sales by providing revenue to plant-based companies for R&D and other expenses.
Interesting, then I figure it probably substituted for meat consumption at restaurants rather than meat consumption at home. Regardless, I think it’s mostly valid to use increase in plant based consumption as a proxy for a reduction in meat consumption since total food consumption is relatively stable.
UK vegan product sales (where Veganuary is most active) went down overall in 2023. This article from Nov 2023 highlights this fact and attempts to reconcile them in the context of outside economic forces.
However, we do have to consider that meat consumption is increasing and plant-based product sales are decreasing in most countries. So it is still very possible that Veganuary guarded against even worse outcomes in the UK.
There’s this in the abstract:
“Average weekly unit sales of plant-based products increased significantly (57 %) during the intervention period (incidence rate ratio (IRR) 1·52 (95 % CI1·51, 1·55)). Plant-based product sales decreased post-intervention but remained 15 % higher than pre-intervention (IRR 1·13 (95 % CI 1·12, 1·14)). There was no significant change in meat sales according to time period. The increase in plant-based product sales was greatest at superstores (58 %), especially those located in below average affluence areas (64 %).”
From the main body of the text: “Plant-based products represented 0·011 % of product unit sales in the pre-intervention period. This increased to 0·016 % during the intervention period and 0·012 % in the post-intervention period. Meat products represented 26·52 % of sales in the pre-intervention period, 26·51 % during the intervention period and 26·32 % in the post-intervention period. The remainder of sales were represented by non-meat products (73·47 % in pre-intervention and intervention periods, 73·67 % in the post-intervention period).”
One thing to flag on reading into this as evidence against plant-based sales leading to lower meat consumption is how much harder it will be to detect a significant effect on meat consumption. The background variation on those is much higher so to detect a significant effect from a campaign like Veganuary we would need a much larger total effect size. Even if the 0.05% of pre/post change in plant-based came 100% from meat I’d expect it still would not be significant.
This can still be a counterfactual decrease in meat sales right?
Agreed, though if their model isn’t correctly specified to identify the causal effect on meat (which I agree is tough here), then presumably the effects on plant-based sales would also be suspect.
Thank you for your investigation.
That is disappointing...
However, there’s still at least some benefit from increased plant-based product sales by providing revenue to plant-based companies for R&D and other expenses.
Yes, good point
Interesting, then I figure it probably substituted for meat consumption at restaurants rather than meat consumption at home. Regardless, I think it’s mostly valid to use increase in plant based consumption as a proxy for a reduction in meat consumption since total food consumption is relatively stable.
@Karthik Tadepalli see my comment below:
However, we do have to consider that meat consumption is increasing and plant-based product sales are decreasing in most countries. So it is still very possible that Veganuary guarded against even worse outcomes in the UK.