Over time, we have become aware of how chemical pesticides impact our bodies. Some shoppers navigate the produce aisle with a cheat sheet of the Dirty Dozen—the fruits and vegetables with the highest levels of pesticide contamination from conventional farming. Today, Earth Day, is an ideal occasion to examine how the food we eat impacts not just our bodies but the world around us, and how to craft a diet that is better for both our planet and ourselves.
When considering the of our food choices, many of us are concerned with emissions involved in transporting our food over thousands of miles. You may think that the locally grown berries have a smaller impact, but consider the cumulative effect of a farmer driving her small truck of mixed produce to six markets each week—along with a handful of other farmers. Compare this to a fully loaded tractor-trailer stocking regional distribution centers near major highways. Thanks to the economies of scale, the environmental effect of transporting each pound of berries on the big truck is minimal compared to each pound from your local farmer.
However, transportation represents just over one-tenth of the environmental impact involved in getting food from a seed in the ground to a plate on your table. The vast majority of greenhouse gas emissions come from food production on the farm itself—and not from growing vegetables.
Raising animals for food is an inefficient use of our natural resources; it takes almost 40 times as much energy to produce a calorie of meat as it does to produce a calorie of grain. But there is another surprising environmental impact: the large quantity of methane produced by cattle, sheep and other ruminants raised both for their meat and for dairy production. I am not suggesting we all become vegan or even vegetarian—that is not a step I am ready to take now, if ever. We can bring about great change by just slightly reducing our reliance on animal products, specifically red meat and dairy. According to a recent paper on the ecological impact of food choices in the United States, the average household could achieve a greater reduction in greenhouse gas emissions by substituting chicken, fish, eggs, and vegetarian protein sources for less than one day per week’s consumption of red meat and dairy products than it would by buying only locally sourced food. The Meatless Monday movement is one structure for converting the one-day-per-week measurement into a practical reality.
After considering carbon emissions and, perhaps, avoiding the dairy section, you are still left with the decision of which produce to buy. Grown without persistent chemical fertilizers, herbicides and pesticides, organic produce seems to have the environmental edge over conventional, and government and independent certification assures that producers meet a set of minimum standards. But large, industrial organic farms may not be much better for the environment than their conventional counterparts. In order to maximize short-term profit, many of these farms plant a single crop over many acres in a practice known as monoculture, which quickly depletes the soil of its nutrients.
A small farm is more likely to grow a variety of produce and rotate crop locations from year to year, which helps maintain a balance of nutrients in the soil. Some of these smaller farms are certified as organic, but many are not. Among the latter, some simply cannot afford the cost of inspection and yearly recertification. Others would face financial ruin if they were forced to lose a season’s worth of tomatoes due to limitations on certain chemical treatments. As an alternative, many local farms practice integrated pest management. While IPM favors organic methods of pest control, it allows for some use chemical pesticides, in a way that minimizes environmental damage and human health risk. This system helps preserve small farms while promoting environmentally sound farming practices.
Whether they are officially recognized as organic or IPM, many small farms engage in sustainable agriculture. While other, often larger, farms bring in fertilizer and cart away their waste, a sustainable farm operates as a nearly closed ecosystem, with using of natural resources efficiently and returning waste products to the soil.
Sustainable farming is an honorable choice—but it is, notably, a choice. On the larger scale, we have no such choice; the Earth is a closed ecosystem, and there is no interplanetary market for fertilizers to replenish our soil. The planet’s health and our own go hand in hand, and we are lucky that the food choices that are better for us are often better for the Earth as well.
For some practical tips on Loving the Earth and Your Food, check out the special tips page for this article.