Guide to Low-Carbon Eating
Sensing growing public concern about the climate crisis, executives at PepsiCo, owner of the Tropicana juice brand, last year asked a simple question: How much carbon does a half gallon of orange juice add to the atmosphere?
The answer was about 3.75 pounds, the same as driving a car 3.75 miles. The bigger surprise, according to the project, is that the impact of getting OJ from grove to kitchen table doesn't come from transportation, but from growing the fruit in the first place. Just 22% of each half gallon's carbon dioxide emissions come from distribution, while production accounts for 60% of all emissions, over half of which can be traced to the use of nitrogen fertilizer.
The research highlights two important points we'd all be wise to consider: What we choose to eat has an enormous impact on our carbon footprint. And in most cases, where our food comes from isn't as important as the kinds of products that we choose to put in our shopping carts.
Food is an often overlooked component of our carbon footprints, but it's one to which we should pay attention. The average family uses almost as many resources staying fed as it does staying sheltered. The diet of the typical household generates about eight metric tons of greenhouse gases (GHGs) each year or about twice the emissions of a car getting 25 mpg and driven 1,000 miles a month.
Though the average meal in the U.S. travels some 1,500 miles before it is served, researchers at Carnegie Mellon University have found that a full 83% of its GHG emissions come simply from growing and raising that food on the farm. Transportation accounts for only 11%, and transportation between the grower and the seller, which is the portion of the equation that's largely zeroed out by eating locally-produced foods, is responsible for a scant 4%.
Figures like these show that reducing the impacts of our diets isn't as clear cut as it might seem. So what's a concerned diner to do? Here's our advice:
- Reduce your consumption of red meat, which alone is responsible for 30% of our country's total food production-related GHG emissions.
- Cut back on dairy products, too, which account for another 18%.
- Focus your protein consumption on chicken, fish, and eggs, which together account for just 10% of food-related GHG emissions. Replacing red meat and dairy products with chicken, fish, or eggs for just one day a week, for example, would yield the equivalent of driving 760 fewer miles each year.
- Fill up on fruits and vegetables, which create just 11% of the GHGs on the nation's plate. Going vegetarian one day per week would be like driving 1,160 miles less per year.
- Buy locally-produced food whenever you can.
- Buy organic foods. Healthier organic soils are able to absorb and store far more carbon than chemically-treated soils. By some estimates, we could remove 580 billion pounds of carbon from the atmosphere simply by growing all our corn and soybeans organically.
- Watch your waste! Buy in bulk and avoid heavily packaged products. We can each prevent the release of 1,200 annual pounds of C02 simply by cutting our garbage output 10%. When it comes to cooking, prepare only what you'll actually eat and clean your plate. Save all your leftovers for other meals and throw out as little as possible.
- Similarly, skip the junk and snack foods, and other heavily processed products. These all take more energy to make than raw foods prepared at home.
- Buy fresh foods rather than frozen foods, which require ten times more energy to produce.
- Eat foods in season. Out-of-season foods transported from distant locales have much larger carbon footprints than those grown nearby. Can, dry, and freeze fruits and vegetables during local harvests so you can enjoy them all year round.
- If you buy non-local, assess the impact. Foods transported by ship have a far lower GHG footprint than those that are trucked or flown. So a Boston resident, for example, is better off drinking wine from France than California, while someone in St. Louis should opt for the West Coast choice. Non-local fresh foods like fruits and vegetables are likely to have been flown in while packaged foods from overseas will most likely have arrived by water.
Being mindful of strategies like these will lower your family's ecological footprint and make sure that what's for dinner is a big helping of positive change!
If you'd like to examine your diet's specific carbon footprint, there are a number of online calculators you can use. We like the one provided by the Berkeley Institute of the Environment, which looks at all aspects of our lifestyles. The Low Carbon Diet maintains a food-only calculator that's also useful. And though it's designed for U.K. residents only, the Food Carbon Footprint Calculator can also provide some helpful insights.