Whether you believe in climate change, like the majority of scientists, or believe it’s a hoax created by the Chinese to make U.S. manufacturing non-competitive, like Donald Trump, the fact is that in most discussions of mankind’s environmental impact, food production is overlooked. Agricultural activities represent 24 percent of all global greenhouse gas emissions annually, with livestock-related activities comprising nearly 80 percent of those agricultural emissions — so if the U.S. population decided to forgo eating cheese and meat for just one day a week for one year, it would be the equivalent of not driving 91 billion miles, or taking 7.6 million cars off the roads. Small changes in our collective diets can have far-reaching effects.
Though carbon monoxide tends to get all the attention, it represents just 9 percent of emissions in the entire agricultural sector, with methane (CH4), a greenhouse gas 25 times more potent than carbon dioxide, representing between 35 to 45 percent, and nitrous oxide (N2O), 300 times more potent than carbon dioxide, accounting for somewhere in the range of 45 to 55 percent each year.
Methane, the byproduct of ruminant animals’ (think cattle and sheep) digestion processes, is primarily released into the atmosphere from said processes (i.e., cow burps), and as the heaping piles of manure from confined feeding operations (i.e., “factory farms”) decompose. When you consider that U.S. livestock in confined feeding operations generate about 500 million tons of manure a year, three times the amount of human waste produced by the entire U.S. population, you can begin to imagine what our insatiable appetite for meat means for the environment (not to mention the contaminating effect manure has on our water supply). Meanwhile, nitrous oxide, also a byproduct of manure decomposition, is primarily emitted during the production and application of nitrogen fertilizers, as well as during the decomposition of carbon-rich soil deforested to create space for agricultural use. About 149 million acres of cropland, 167 million pounds of pesticides and 17 billion pounds of fertilizer are required just to feed these animals.
By now, you’re probably starting to realize that the steak frites, ricotta gnocchi, cheese and charcuterie platter, baby lamb chops and braised short rib on many restaurant menus aren’t doing the environment a whole lot of good. Don’t blame factory farming, slaughterhouses (eight slaughterhouses are consistently among the nation’s top 20 industrial polluters, responsible for discharging 30 million pounds of contaminants, primarily nitrates), supermarkets and restaurants just yet, though. They’re only reacting to our appetite, which is devouring meat at historic rates. From 1971 to 2010, while the global population grew 81 percent, worldwide meat production tripled to approximately 600 billion pounds.
So, which foods are doing the most damage? The Environmental Working Group Meat Eater’s Guide to Climate Change and Health recently concluded a comprehensive study that analyzed the “cradle-to-grave” carbon footprint (emissions generated before and after the food leaves the farm, from the pesticides and fertilizer used to grow animal feed to the grazing, animal raising, processing, transportation, cooking and disposal of unused food) of 20 popular types of meat, dairy and vegetable proteins. Lamb, beef and cheese had the highest carbon footprints (in that order) — no surprise there. The rest of the list, in order: pork, farmed salmon, turkey, chicken, canned tuna, eggs, potatoes, rice, peanut butter, nuts, broccoli, tofu, dry beans, milk, tomatoes and lentils. Though the last few may surprise you, keep in the mind that lamb generates 86.4 pounds of CO2 per kilogram eaten, beef creates 59.6 pounds, cheese produces 29.7 pounds, while lentils (1.98 pounds), broccoli (4.4 pounds) and tomatoes (2.42 pounds) generate far less, with most of their emissions coming from transportation, cooking and waste disposal.
If the environmental impacts of our diets aren’t enough to curb our appetite for meat and dairy products like cheese, maybe the impact on our health might. As a National Cancer Institute study of 500,000 Americans found in 2009, people who ate the most red meat were 20 percent more likely to die of cancer and at least 27 percent more likely to die of heart disease than those who ate the least. In women who consumed the most meat, the risk of dying from cardiovascular disease was 50 percent higher.
Going vegetarian, or simply slowing down our consumption of meat, isn’t as drastic a lifestyle decision as one may assume, either. An analysis of data from the Economic Research Service of the United States Department of Agriculture (ERS/USDA) by Shrink That Footprint found that 60 percent of our diets are identical, regardless of whether one is a “meat lover,” “average,” “no beef,” “vegetarian,” or “vegan.” Though a “vegetarian’s” CO2 emissions were a third lower than that of an “average” American and almost half that of a “meat lover,” the analysis found that simply eating chicken instead of beef cut a quarter of CO2 emissions. The effects of such a small change begin to make sense when one considers that while animal products account for just 25 percent of caloric intake, they constitute 60 percent of food-related emissions.
For those who worry they won’t get enough protein if they ditch meat, consider a recent National Health and Nutrition Examination Survey, which found that while the recommended daily allowance of protein for men ages 19-70 was 56 grams per day, men in this age group consumed almost twice that amount, at an average rate of 88.3 to 109.2 grams per day. Then, compare that figure with another study’s findings that only 1 percent of children and 4 percent of adults ate their recommended daily intake of fruits and vegetables, and you start to understand the logic behind going vegetarian.
Besides eating less meat, you may wonder how you can help to become part of the solution rather than the problem. The answers are right in front of you, and you’ve probably heard them before. Buying locally grown produce like broccoli can reduce its emissions by as much as 20 percent, and up to 25 percent for tomatoes. Buying organic helps too, as organic farming methods for both crops and animals have a much lower impact on the environment than conventional methods, with organic-certified farms required to use natural methods for soil fertilization, weed prevention and pest control. In addition, foods cannot be labeled organic if antibiotics or growth hormones are used, if they are genetically modified or irradiated, and if certain standards of care are not met with regard to the treatment of livestock.
But if we are to make a truly significant difference, it may come down to simply curbing our enthusiasm, and appetite, for meat. If your four-person family skips steak just once a week, it’s the equivalent of taking your car off the road for nearly three months. Chew on that.