As the holiday season approaches, deciding what to put on your plate takes on new significance—not only for your health, but for the health of the planet.
Does your Thanksgiving dinner make any difference in the vast and complicated context of greenhouse gas emissions and climate change? No, really: does it? That’s the question at the heart of “sustainable eating”—one that experts from the fields of nutrition, culinary arts, and environmental science are eager to answer.
Sustainable eating is, in the broadest strokes, a practice: choosing foods based on their impact on both the health of the planet and your body. At the recent Harvard T.H. Chan School of Public Health event Eco Gusto! Harvesting a Healthy & Sustainable Holiday, featuring demonstrations of how to prepare a healthy appetizer and a festive mocktail, professor of nutrition and epidemiology Edward Giovannucci commented on the links between diet and disease prevention. Nutritionists often point out that diet affects risk for chronic illness, but one statistic stands out starkly: one-third of cancer cases can be prevented through good lifestyle choices. As Giovannucci notes, many positive dietary choices can be framed in terms both of not just eating “healthy” in the abstract, but specifically eating combinations of plant-based food—foods which are proven to reduce blood pressure and levels of low-density lipoprotein (LDL) cholesterol, or “bad” cholesterol (implicated in heart disease). For the holiday table, he says the key is simplicity: “Eat more fresh, whole plant-based foods, and eat less processed food.”
Much of modern cuisine is, in a sense, a type of art: so, while the recipe for your sister’s favorite pumpkin-pecan pie may be complex, the ingredients shouldn’t be. If possible, limit processed store-bought crusts, fillings, and pre-packaged meals: these items and others like them are often high in sugars, unhealthy fats, and artificial additives, and they have a high environmental cost in terms of greenhouse gas emissions (GHG). Christopher Golden, a professor of nutrition and planetary health, notes that food production— from farming practices to transportation and waste—accounts for about one-third of global GHG emissions. (In the United States, 35 percent of food produced is never eaten; see “The Food-Climate Conundrum.”) Most plant-based foods have a far lighter environmental footprint to produce, and—if waste occurs, especially around the holidays—to throw away. Golden argues that consumption must shift toward food systems that stay within “planetary boundaries”—with limits on water use, carbon emissions, and consumption of other critical resources. Quite simply, he says, “We need to rethink how we produce food.”
But acknowledging that the logistical, economic, and environmental challenges of food production can’t be resolved before this Thanksgiving, what conscious choices can every person make to reduce their carbon footprint at the dining table?
Reducing red meat consumption, especially beef and lamb, is one of the most effective ways to lessen human impact, says Golden. Producing these meats is resource-intensive, consuming large volumes of water and contributing significantly to GHG emissions: beef production, for example, produces five times the amount of GHG and six times as much water-polluting reactive nitrogen as other livestock categories, which each contribute more GHG than crops for human food (see “Eating for the Environment,” March-April 2017).
For the holidays, then, Golden suggests rethinking the emphasis on turkey, ham, or roast beef. “The veggie dishes, stuffing, and pies are often more delicious and nutritious, and they’re better for the environment,” he says. So, must holiday dinners remove meat entirely from the menu?
No. Golden acknowledges that not all animal products are equally damaging to the environment, and many are extremely healthy. For those who still want to include animal products in their diets or on their Thanksgiving table, he points to more sustainable options such as farmed salmon, free-range chicken, and shellfish.
“Sustainably farmed seafood and poultry have a lower environmental footprint and can still provide essential nutrients,” Golden notes. In fact, shellfish is proven to be one of the healthiest meat options one can consume, with mussels, clams, and scallops especially rich in protein, vitamin B12, omega 3 fatty acids, zinc, and iron.
This point underscores that small changes in the types of animal products consumed can make a difference. The Thanksgiving turkey may be a focal point layered in four centuries of American, colonial, and pre-colonial history, but the Pilgrims and Wampanoag ate eels and shellfish, including lobster, clams, and mussels, at their Thanksgivings, too–so there is no historical reason you can’t follow suit.
Graceanne LaCombe, who works on sustainability projects at the Barilla Foundation and ALMA, the School of Italian Culinary Arts, echoed these ideas at Eco Gusto!, drawing on her own experiences in culinary education. LaCombe’s work focuses on helping chefs understand the environmental impact of the food they prepare.
ALMA has recently produced a series of food sustainability initiatives, including a project developed together with the University of Parma and ALMA’s Culture and Sustainability Faculty exploring regional Italian recipes from author Anna Gosetti della Salda's 1967 book Le ricette regionali italiane. The project showed how the older, less processed recipes in Gosetti della Salda’s book often have a smaller environmental footprint.
As she introduced the dish that was being prepared for the event (see “Barley Recipe (Orzotto) by Chef Mario Marini”), LaCombe presented another food sustainability project that ALMA has been a part of for the last three years: the LIFE Climate Smart Chefs project, guided by the Barilla Foundation. To assess the sustainability of different dishes, including Chef Marini’s orzotto, LaCombe and the LIFE Smart Chefs Project developed a tool called the Nutritics’ Foodprint calculator—which LaCombe says is the only scientific tool that has been created to rate the sustainability of recipes. The tool calculates where food is coming from, how it’s being cooked, and the output of everything in terms of carbon and water emission levels before giving a final sustainability score. The goal, ultimately, is to help food businesses move toward optimizing consumer preferences and environmental impact in products.
LaCombe and her team also developed a set of functional sustainability guidelines—ALMA’s “Healthy and Sustainable Guidelines,” which are currently being used by the Union of European Football Association (and were used across stadiums at the 2024 UEFA European Football Championship) as a resource to help teams, sports event organizers, caterers, and companies offer more sustainable catering services at athletic events. Coincidentally, as was discovered prior to Eco Gusto!, these sustainability guidelines are not only more environmentally friendly, but almost identical to the guidelines for cancer prevention compiled by the Zhu Center. Together, these initiatives underscore a key takeaway: plant-based healthy eating can be, when done correctly, substantially better for both you and the planet.
As LaCombe explained, ALMA’s work on food sustainability is “a retrospection and demonstration of where we’re headed and what we should be looking at.”
Learning How to Be “Green and Healthy”—for This Thanksgiving
In both the long-term and the short-term (at your Thanksgiving table), not all plant-based diets are automatically healthier or more sustainable. As Erin O’Donnell writes in “Live Long—and Save the Planet” (March-April 2023), unhealthy plant-based diets—just excluding animal-based foods and replacing these foods with “vegetarian” white-flour breads, pastas, and fruit juices—actually boost the risk of cardiovascular disease (see the Nurses’ Health Study II).
Ultimately, sustainable eating shouldn’t be thought of as a fad, or a trending social or cultural movement. Rather, it’s about the realities of how foods, as a source of physical fuel, contribute to your biological health. And it’s about the realities of where those foods came from, and the journey they took to make it to your Thanksgiving dinner.
Eating sustainably isn’t about denying the joy of eating, or the shared experience of the holidays. It’s about being more deliberate, more mindful, and more aware of how food is sourced, prepared, and consumed.
