Mic the Vegan, a well-known voice in the plant-based community, recently responded to claims made in the book Why Vegans Have Smaller Brains: And How Cows Save the Planet. The book was promoted in a YouTube interview by carnivore diet advocate Dr Anthony Chaffee.
Mic dissected the brain and environmental claims in detail, exposing inaccuracies and highlighting the misleading nature of their arguments. You can watch his video, and find a summary of some of his key points, below.
The brain shrinkage claim
Despite what the book’s headline suggests, there is no legitimate scientific evidence that vegans have smaller brains. In the interview, the authors cite a 2008 study. However, Mic points out that this study never mentioned vegans, meat-eaters, or dietary habits at all. “This was a study that looked at B12 levels and brain shrinkage over five years,” he explains. Conducted on just over 100 elderly individuals in the UK, the study explored the correlation between B12 deficiencies and brain atrophy, not dietary patterns.
Mic also notes that in the early 2000s, the likelihood of finding a significant vegan population in the UK was slim, meaning it was highly unlikely there were vegans in the study. “This is a gross misrepresentation of the science,” he says. He further clarifies that brain shrinkage can result from various factors, including alcoholism, malabsorption, and certain medications, all unrelated to a vegan diet.
Read more: Plant-Based Meat Cuts Environmental Impact by 89%, Study Finds
Vegans and B12 today
While older studies suggested vegans had lower B12 levels, newer research tells a different story. Mic cites a German study that found vegans often have comparable B12 levels to meat-eaters due to regular supplementation and fortified foods. “My B12 levels are higher than the average meat-eater,” he shares, attributing this to accessible vegan-friendly supplements.
The Ornish and vegetable consumption studies
Mic highlights a randomized controlled trial by Dr. Dean Ornish, which demonstrated improvements in Alzheimer’s patients on a plant-based diet. Since Alzheimer’s is closely linked to brain shrinkage, the findings contradict the idea that plant-based diets harm brain health.
Additionally, a 2018 study involving 850 participants found that vegetable consumption was strongly associated with reduced brain shrinkage. Mic notes that vegetable consumption was the food group most statistically and powerfully linked to less brain atrophy. This directly counters the carnivore proponents who advocate for zero vegetable intake.
Environmental claims: cows and the climate crisis
The book claims that farmed cows are environmentally harmless. Mic calls this argument “blatantly false,” pointing out that the Food and Agriculture Organization (FAO) attributes 14.5 percent of human-driven greenhouse gas emissions to animal agriculture. Other estimates place the figure even higher.
Mic debunks the idea that the methane emitted by ruminants doesn’t contribute to climate change because it is part of the natural carbon cycle. Methane, he explains, has a global warming potential 32 times greater than CO2 over 100 years and 86 times greater over 20 years.
Soil and carbon sequestration
The book argues that grazing animals improves soil health and sequesters carbon. Mic references studies showing the opposite. A study from Tibet found that areas excluded from grazing had double the soil organic carbon compared to grazed areas. Mic adds that even grazing systems that store some carbon are eventually carbon-positive due to methane emissions. He also highlights the soil carbon saturation limit, which prevents grasslands from indefinitely storing carbon.
Sheep Farming and Land Use
One author praises sheep farming in the UK, but Mic points to journalist George Monbiot’s critique of how overgrazing has “sheep-wrecked” the country’s landscapes. Monbiot compares the impact of sheep farming in the UK to cattle farming in the Amazon, which has caused significant deforestation. Mic emphasizes that grazing animals often leads to habitat destruction rather than ecological restoration.
Read more: Deforestation Could Turn The Amazon Rainforest Into A Permanent Source Of Carbon