A paper was published this week looking at meat and dairy alternatives [1], [2]
The conclusions were clear.
When looked at from nutrition, health, environmental impact and cost perspectives, “unprocessed plant-based foods such as peas, soybeans, and beans performed best in our assessment across all domains”
And even processed plant foods were still better than animal products, although to a lesser extent
“Reducing meat and dairy intake has been identified as a necessary strategy for mitigating the high environmental impacts food systems are currently having on climate change, biodiversity loss associated with land-use changes, and freshwater use”
The word “necessary” is significant. Diet change is not optional for a sustainable planet. This cannot be said too often
The paper does not advocate a vegan diet, and does not discuss the full range of animal products, but it does provide very strong support for anyone considering a vegan diet.
The research was conducted with a focus on high-income countries
Here are some highlights from the paper
Nutrition
Unprocessed plant-based foods such as peas, soybeans, and beans performed best
Meat products and milk have high levels of saturated fat. Replacing all calories from meat or dairy with alternatives reduced nutritional imbalances
Most of the changes in nutritional imbalances were from reductions in saturated fat (41%), and from increases in fiber (20%) and potassium (12%)
Health
High red and processed meat intake and low intake of nuts, legumes, and whole grains have been associated with increased risk for chronic diseases such as heart disease, stroke, and cancer
All meat and milk alternatives were associated with reductions in chronic disease risk
Environment
The environmental impact of food was considered in three areas: Greenhouse Gas emissions, land use and water use. In addition comparisons were made in two ways, first by replacing equivalent servings of a food type, second by replacing calorie intake.
All meat and milk alternatives had lower environmental impacts per serving than the comparable meat and milk products.
The numbers here are striking:
Compared to beef the impacts of meat alternatives ranged from 2% for soybeans and peas (GHG: 1%, land: 3%, and water: 5 to 8%)
Replacing all calories from meat or dairy with alternatives reduced the average environmental impacts by up to 40% when replacing meat and up to 16% when replacing dairy
There were a few exceptions. Replacement with almond milk (of which four servings are needed to replace one serving of milk) increased average impacts by 14% (GHG: 3%, land: 0%, and water: 67%), driven by high increases in water use.
This was expected as the high water requirement of almond milk is well known
Cost
Replacing all calories from meat or dairy in high-income countries with alternatives decreased costs by up to 6-36% for unprocessed alternatives, and it increased cost by up to 26 to 37% for processed alternatives
The greatest reductions among the meat replacements were for soybeans, beans, and peas (35 to 36%)
Synthesis
The results of the comparisons above were combined into a single measure
Unprocessed plant-based foods were the best overall performers for replacing meat and dairy in high-income countries. Out of a possible summary score of 100, soybeans, peas, and beans attained scores of 93 to 97 for replacing meat
Beef performed worst overall (13) and on health, GHG emissions, land use, and water use
Conclusion
Unprocessed plantbased foods such as soybeans, peas, and beans are best suited for replacing meat and dairy in high-income countries, and performed well on all dimensions.
In comparison, processed plant-based foods such as veggie burgers and plant milks were associated with lower climate benefits and greater costs than unprocessed foods, but still offered substantial environmental, health, and nutritional benefits compared to animal-source foods”
It was noted that uptake of plantbased diets will not automatically follow as a result of these findings. There need to be public awareness campaigns and better alignment of subsides
“The livestock sector holds considerable political influence in many markets and various interest groups aim to influence the political debate”
Reviews
The report has received mixed responses. One reviewer smugly claimed that the report was a wounding blow to vegans because almond milk has a high water footprint. But as George Monbiot points out, the water footprint of dairy milk can be higher if the water required to grow cattle feed is taken into account [3]
Nevertheless, the paper does show that vegans have to make choices and compromises. There is no perfect diet – diets will rate better on some criteria and worse on others. But the main point is that only a diet that is very low in meat and dairy, or excludes them altogether, will help to mitigate the impact of our food systems on climate and health.
The Conversation gave an interesting comment, “But a surprising runner-up was tempeh, a traditional Indonesian food made from fermented soybeans, which retains much of the nutritional properties of soybeans without much processing or additives. This, and its relatively low cost, gave it an edge over more processed alternatives such as veggie burgers” [4]
References
[1] A multicriteria analysis of meat and milk alternatives from nutritional, health, environmental, and cost perspectives
https://www.pnas.org/doi/epub/10.1073/pnas.2319010121
[2] Marco Springmann
https://www.oxfordmartin.ox.ac.uk/people/dr-marco-springmann
