All I Want for Christmas is a Vegan USA: New Data, Conflicting Headlines

While the tsunami of people adopting a vegan diet, including many professional athletes, in the wake of the viral movie What The Health is notable, it is quite a leap to discuss the day when all citizens of the US will shun animal products and eat only plants. However, 2 scientists from the USDA and Virginia Polytechnic Institute (with some prior research support from the dairy industry) published projections on the impact of an immediate switch for all US citizens from beef to beans. When scenarios have previously been analyzed for the entire world , the projections a vegan approach to food production. The headlines following the publication of this academic paper ranged from comments about a “public health disaster” to “mixed results” to “crappy reasons” it would not work (due to our need for manure). While this new study is far from easy to digest, akin to putrefaction of meat in our colon, it is worth a look at the data.

The new study was published this week in the Proceedings of the National Academy of Sciences. The impact on nutrition and greenhouse gas (GHG) production from suddenly eliminating all animal products from US agriculture were quantified. Some findings mentioned in the analysis include:

1) In the overall US diet, animal-derived foods currently provide energy (24% of total), protein (48%), essential fatty acids (23–100%), and essential amino acids (34–67%). These were target nutrients to be replaced by plant foods.

2) The US livestock industry employs 1.6 × 106 people and accounts for $31.8 billion in exports. Livestock recycles human-inedible food and fiber processing byproducts, converting them into human-edible food, pet food, industrial products, and fertilizer. There would need to be a plan for

3) Models of the new plant-only agriculture predicted 23% more food production available for the hungry and for export. Despite more available food, the production was projected to meet fewer of the US population’s requirements for essential nutrients like vitamin B12 and essential fatty acids.

4) In the projected agricultural system with no animals, estimated GHG decreased (28%) from 623 million tons to 446 million tons per year.

Does any of this strike you as a health disaster, recognizing this is just a hypothetical analysis and not what McDonald’s is planning to announce tomorrow? A reduction in GHG by over 1/4 and and increase in food by 1/4?

Possible nutritional deficiencies resulting from a vegan diet across the USA generated headlines. The research data is in figure 2 of the paper. There are 38 nutrients reported on for the present food system and a plant only system. It is noteworthy that 32 of the 38 nutrients were projected to be of adquate supply in a vegan America. Indeed, some like total energy, protein, magnesium, selenium, zinc, vitamin K, vitamin E and thiamine were all higher in the plant scenario. Only vitamin B12, vitamin D, vitamin A, calcium, and essential fatty acids were predicted to be an issue and all are well known and easily addressed with vegan friendly multivitamins already commercially available.

Is there more good news to consider for a vegan USA? The plant-only diet was projected to substantially reduce daily costs of food compared with animals diets (figure 4 of the paper). The drop in projected production of GHG is in agreement with a survey study of 13,000 American diets that reported that consumption of more plant protein foods and less animal protein foods produced diets with low GHGs based on current carbon footprints of food. Other studies have also concluded that plant-based foods have reduced environmental impacts compared with animal-based foods, and that switching to a plant-based diet confers environmental benefits.

Overall, it seems that scary headlines about a looming public health disaster are a bit overstated, particulary in view of the fact that this is a simulation, not the national food policy starting tomorrow. Some experts in the field even commented that the reductions in GHG estimated in the new paper may be too conservative and more impressive numbers could be achieved with a global land policy.

So what to do now? At a minimum, adopting a Meatless Monday strategy could remove 4 million cows a year from food production. Eating vegan before 6PM, as suggested by author Mark Bittman, can cut animal food intake by 2/3rds. Or download What The Health one more time and go full out vegan 24/7/365 like so many are doing (including so many pro athletes that NBA seems like the NVA).