The American diet and the American waistline are expanding, and the effects are drastic. Concurrently, the world’s population is expanding, and competition for natural resources (soil, land, energy, water, air) is intensifying. All these events are linked through their impact on the environment.
Regardless of what you think about global warming, you’ll likely agree that the American lifestyle, advancements across the globe, and the world’s ballooning human population are affecting the state of the planet. But all is not lost; there are plenty of easy changes you can make to your daily diet and training regime that will reduce your carbon footprint while improving your health.
The American Carbon Footprint
People in the know talk often about carbon footprint. Simply put, carbon footprint is a way to measure the impact that human activities have on the environment through greenhouse gas emissions (GHGEs). GHGEs—namely, carbon dioxide (CO2), methane, nitrous oxide and chlorofluorocarbon—are associated with climate changes and have an impact on the entire environment. The more dependent we are on fossil fuels, the larger our carbon footprint is.
Predictably, Americans are responsible for more than 20 tons of CO2 per capita annually (Walsh & Sharples 2008). How does that compare with the rest of the world? A recent study by researchers at the Massachusetts Institute of Technology found that even a homeless American has an average carbon footprint of 8.5 tons of CO2—more than twice the global average of 4 tons (Walsh & Sharples 2008; Geagan 2009).
Eating Green vs. the American Diet
According to the United Nations Food and Agriculture Organization, the typical American diet now weighs in at more than 3,700 calories per day (Tidwell 2009) This Western style of eating—usually loaded with red meat, processed meats, refined grains and sugars, animal fats like butter and cheese, high-calorie liquids, heavily processed foods and convenience foods—is not at all “hybrid” in style, to use an auto design analogy. Instead it can be more accurately described as an SUV style of eating. Similar to many gas-guzzling, off-road vehicles, the Western diet is extravagant in regard to fuel use and emissions.
Along the same lines, this “Hummer” style of eating is high in calories and low in whole grains, beans, fruits and vegetables; as such, it is associated with high rates of obesity and chronic diseases. Conversely, a green (or low-carbon) diet calls for consumption of locally grown and seasonal food items, greatly reduced intake of meat and dairy, avoidance of processed and packaged foods, and an overall focus on reducing food waste.
The American Diet and GHGEs
If you’re asking, “How, exactly, can one’s diet and waistline affect the environment?” here are some points to ponder. While Americans don’t stroll around continually “emitting” greenhouse gases the way ruminant animals do, we indirectly cause vast amounts of GHGEs every day. Owing to our driving habits and excessive consumption of various natural resources, we have an enormous carbon footprint compared with the rest of the world. By making small, sustainable changes, beginning with our diet and activity habits, we can start to move toward a “green” way of life. In essence, by eating and existing with the planet in mind, we can effectively reduce GHGEs and “be green.”
The way we eat—including our food choices, portion sizes and lifestyle (dining out vs. cooking at home; frozen commercial casserole vs. homemade lasagne)—has a significant impact on daily GHGEs; food production accounts for one-third of GHGEs on account of the many steps it takes to get food from farm to table (Geagan 2009; Harmon & Gerald 2007). Steps in food production include harvesting, processing, heating and cooling, storage, packaging and transportation (Harmon & Gerald 2007). Some food items go through many of these steps multiple times.
For example, consider the 350+ million acres of cropland that exist in the contiguous 48 states, some of which are devoted to growing corn (NRCS 2007). When a corn crop is harvested, the end use determines how and where it is processed. For example, if the end product is corn syrup, the crop is transported to a facility where each ear of corn is processed and heated until every kernel is transformed.
After this conversion takes place, the syrup is packaged and transported to another facility, where it is stored at the proper temperature (heating and cooling come into play) until it is needed to sweeten or even thicken an item. At this point, the corn syrup is transported to yet another facility, where it is added to other (processed) items in order to make the final product. Corn syrup is commonly used as a sweetener in processed foods like ice cream or commercial cookies. The final product—be it cookies or ice cream or something else—also requires processing, heating or cooling, storage and transportation, and it may be stored and transported many, many more times before it arrives on your table. With this one example, it is easy to see what an impact our food choices have on the environment and the positive impact we can make if we reduce our intake of processed and packaged foods.
CDC (Centers for Disease Control and Prevention). 2010. Obesity and overweight. www.cdc.gov/nchs/fastats/overwt.htm; retrieved Feb. 8, 2011.
Geagan, K. 2009. Go Green Get Lean. New York: Rodale.
Harmon, A.H., & Gerald, B.L. 2007. Position of the American Dietetic Association: Food and nutrition professionals can implement practices to conserve natural resources and support ecological sustainability. Journal of the American Dietetic Association, 107, 1033-43.
Tidwell, M. 2009. The low-carbon diet. Audubon, 111 (1), 46-66.
Vegetarian Resource Group. www.vrg.org/press/2009poll.htm; retrieved Feb. 3, 2011.
Walsh, B., Sharples, T. 2008. Sizing up carbon footprints. Time, 171 (21), 53-55.