USDA examines a world without farm animals

December 13, 2017

Imagine a world where farmers didn’t raise animals. No cows in the pasture or pigs in their pens. No chickens laying eggs or sheep being sheared. What kind of effect would it have on society? The U.S. Department of Agriculture (USDA) and Virginia Tech set out to answer this question with a recent investigation.

The investigation comes at a time when many are questioning the pros and cons of producing animals for food. Some argue that our society eats too much meat, harming our overall physical health. Some say that using animals for food is unethical. Others worry about the environmental impact of animal production, namely the high level of greenhouse gasses created.

The researchers concluded that whether we eat too much meat or not, completely cutting out animal products would present major challenges in meeting the population’s nutritional needs. Meat, milk, eggs, fish and cheese provide many nutrients that the human body needs.

“Different types of carefully balanced diets — vegan, vegetarian, omnivore — can meet a person’s needs and keep them healthy, but this study examined balancing the needs of the entire nation with the foods we could produce from plants alone,” said animal scientist Mary Beth Hall, a co-leader of the study. “There’s a difference between what’s possible when feeding one person versus feeding everyone in the U.S.”

Foods from plants aren’t as nutrient-dense as foods from animals, so people would need to eat more in order to get the calories and nutrients they need. And for some important nutrients — like calcium, vitamins A and B12 and certain fatty acids — there currently are no plant-based substitutes. Some of these fatty acids provide real health benefits, like reducing the risk of cardiovascular disease and improving cognitive function and vision in infants.

There was one potential positive identified by the study: A 23% increase in available food, as crop farming is an efficient use of space. Much of the land used for animals isn’t suited for certain crops, so it would likely be used for plants like corn and soybeans.

Switching away from animal production would also decrease greenhouse gas emissions, but not by as much as some might expect. In 2015, of the total amount of greenhouse gasses produced by U.S. agriculture, about 49% came from animal production, according the Environmental Protection Agency. One might think that dropping animal production would then drop emissions by the same number, but the figure is estimated to be closer to 28%. This is because producing additional food crops would still create greenhouse gasses, as would producing synthetic fertilizer to replace manure. In the grand scheme of all U.S. greenhouse gas emissions, this would amount to a 2–3% decrease, the agency says.

“A take-home message from the study was that we need to expand the way we think about food production to account for the complex consequences of changing any individual piece within the wider food system,” said co-leader of the study Robin White.

Category: Food Safety, Agriculture