Of all the ways to live more sustainably, tweaking your diet has got to be one of the most impactful. We load up our plates three times a day, after all – and each time is an opportunity to support the food system we’d like to see.

What Does It Really Mean To Eat Sustainably?

“At a very broad level, a sustainable food system protects the planet and its people,” Sujatha Bergen, health campaigns director at the Natural Resources Defense Council in the U.S. says. More specifically, foods that don’t require much water to grow, contribute to land clearing or biodiversity loss, or emit large amounts of greenhouse gases (carbon and methane are two of the biggies in agriculture) tend to be considered more sustainable for the planet.

Of course, truly sustainable diets need to take human livelihoods into account too. “Sustainability encompasses not only the environmental but also the social and economic equity aspects of the food system,” Kristin Reynolds, Ph.D., chair of food studies at The New School and lecturer at Yale School of the Environment explains.

As discussed in Julian Agyeman, Ph.D.’s framework on “just sustainabilities,” areas of environmental injustice also tend to be areas of social injustice and vice versa. It’s no wonder that the United Nations’ second Sustainable Development Goal seeks to “end hunger, achieve food security and improved nutrition, and promote sustainable agriculture.” In order to create a food system that can sustainably feed the world into the future, all these needs must be addressed simultaneously.

Why Is This Important?

The food industry is massive, so reducing its impact will go a long way in helping us avoid the worst impacts of climate change. “More than a third of the land that we use globally is used for agriculture, and about a billion people work in the agriculture sector,” says Bergen. And while one person changing their diet won’t save our planet, director of nutrition at Tulane University Diego Rose, Ph.D., MPH, explains that if everyone did something, the savings would be huge.

In a study published earlier this year, Rose and a team of researchers measured the carbon and water footprint of 16,800 Americans’ daily diets. They found that if the group with the most environmentally taxing diets made just one sustainable food swap a day, it would reduce their diet’s overall daily footprint by up to 48.4%. As Bergen notes, and this research demonstrates, “Even small diet changes can make a big difference.”

What To Know About Meat

It won’t come as much of a surprise that the industrial livestock sector has a major environmental impact. But it’s worth sharing the numbers, just because they’re so staggering: Global livestock production is responsible for 14.5% of human-induced greenhouse gas emissions, according to the FAO, and while it occupies nearly 80% of agricultural land, it provides less than 20% of the world’s calories.

To understand the climate impact of meat, first consider the amount of land that’s required to grow food to then feed to animals. “In many places, there is competition between land use for agriculture and land use for preserving biodiversity and some of our most important forests,” Bergen notes, pointing to regions like the Amazon that show how large-scale animal agriculture can destroy local communities and ecosystems.

Then, you have the emissions of the livestock itself. Ruminant animals (cows, sheep, and goats) are the worst offenders here. They have multiple stomach compartments that break down food through a fermentation process that releases methane—a powerful greenhouse gas that has 25 to 80 times the warming potential of carbon dioxide. “That methane gas is what’s really contributing to their impact,” Rose notes. According to one 2017 analysis, the overall environmental impact of ruminant meat is about 100 times that of plant-based foods. Not to mention, plant-forward diets tend to be healthier than carnivorous ones by most metrics.

Livestock with a so-called monogastric (aka, one-chamber) stomach design (think chickens and pigs) do not emit methane and therefore tend to be a better pick from a sustainability perspective. But of course, the way an animal is raised also affects its overall impact. Grass-fed meat from a small farm that uses regenerative grazing practices will be a better choice for the environment, animal welfare, and human health than meat raised on a feedlot somewhere. Like every other sustainability conversation, this one is nuanced, and it doesn’t have easy answers.

9 Foods That Tend To Be More Sustainable

Now it’s time to explore where all of this leaves us: the hungry consumer with a grocery list. First and foremost, given the complexities of the food system, it’s important to note that no one food is inherently good or bad from a sustainability perspective. Again, it’s all about where it comes from, how it was grown, who grew it, etc. A person’s cultural background and nutritional needs will also affect their ideal diet, and not everyone has access to eco-options, so it’s important not to shame or blame.

With that being said, the following foods tend to have the lowest environmental footprint in terms of water use, land use, and greenhouse gas emissions. If you’re looking to eat more sustainably (and oftentimes, more healthily), this list is a good place to start:

1. Organic Fruit And Vegetables

As mentioned earlier, plants tend to be a lot less resource-intensive to grow than animals. And Bergen adds that organic fruit and vege are even better from an environmental perspective since they aren’t grown using chemical pesticides and fertilizers. Not only do these come with health concerns, but they can also be bad for soil health, made from planet-warming fossil fuels, damaging to nearby wildlife, and threatening to farmworkers. To keep the cost down, she recommends buying organic items listed on the EWG’s Dirty Dozen list as the most-sprayed produce such as strawberries, spinach, kale, collard, and mustard greens currently top the list.

As far as specific produce items that require the fewest resources to grow, onion, celery, potatoes, and carrots topped one 2015 study on the foods with the lowest global warming potential by weight. Food grown outdoors tend to be less resource-intensive than those grown in climate-controlled greenhouses.

2. Regenerative Fruit And Vegetables

Regenerative agriculture takes the organic concept one step further by limiting pesticide use and using farming practices that prioritise soil health. By utilising techniques like crop rotation, composting, and hand tilling, regenerative farms seek to support the natural capacity of soil to pull carbon out of the atmosphere. Studies have even shown that produce grown on regenerative farms boast more nutrients than traditionally grown fruit and vege..

3. Local And Seasonal Fruit And Vegetables

Eating locally and seasonally will ensure that your produce didn’t take a long-haul flight to get to you, making it a straightforward way to cut down on emissions. (Transportation accounts for about 15% of a food’s total greenhouse gas load.) Plus, it’s usually a tastier and fresher way to eat. Joining a local food program like a CSA can help you learn what’s available in your area.

4. Legumes (Lentils, Chickpeas, Beans)

Bergen notes that legumes also tend to be on the lower end of the spectrum of greenhouse gas emissions. Crops like lentils, chickpeas, and beans can also help invigorate farmland with healthy nitrogen, making them a soil-friendly diet addition.

5. Grains

Grains also tend to have relatively low greenhouse gas emissions, with options like rye, barley, and oats requiring less carbon to grow by weight than rice, which has a slightly higher footprint. However, since grains are such a cheap diet staple around the world, they are often grown in monocultures – farm plots that deplete soil health by growing huge amounts of only one crop. Look to buy from smaller, more dynamic farms when you can.

6. Mackerel, Mussels, Sardines, and Anchovies

We could easily spend a whole article diving into the eco pros and cons of seafood, but in short, small seafood tends to be best for human and environmental health. For starters, it is less likely to be overfished in the wild, and it takes fewer resources to farm. Fish that are lower on the food chain will also naturally replenish faster than their predators. They don’t accumulate as much mercury over their short lifespan either.

However, the seafood industry is rife with human rights abus), so it’s important to know where your seafood is coming from, no matter what you’re buying.

7. Seaweed

Seaweed is a crop that requires next to nothing to get started and is quick to grow. Plus, the marine plant can help capture carbon and filter out water pollutants as it spreads. It may even prove useful in reducing the methane emissions of those gassy ruminants.

8. Fungi & mushrooms

Like seaweed, mushrooms are a low-input crop that can grow in inhospitable areas without much fuss – they’re even easy to grow at home. Some varieties also have a meaty texture and taste, making them a nice vegetarian substitute.

9. Nuts

As a category, nuts fall somewhere in the middle of the sustainability spectrum. While some varieties like peanuts (technically a nitrogen-fixing legume) have a pretty low footprint. Others, like almonds, are very water-intensive and tend to be grown in already water-starved areas (California is an example).

10 Less Sustainable Options

The following items tend to have a higher environmental impact. If you’re looking to eat more sustainably, try to consume them in moderation. Remember, even swapping one of these foods a day can make a big difference in your overall food-print.

1. Beef

“In the U.S. diet, beef is the single biggest contributor to global warming emissions,” Bergen says – by a long shot. Rose explains that in his review of the foods that Americans eat that have the highest environmental impact, the top 10 were all beef products. If you’re going to make one change to your diet, swapping a cut of beef for another protein (even another animal, like chicken or pork) is likely the one that will have the largest impact.

Swap for: Plant-based protein, chicken, or pork

2. Lamb

Sheep require even more land to grow and more feed than cows do (on average), and they also emit methane into the atmosphere.

Swap for: Plant-based protein, chicken, or pork

3. Goat

The final ruminant animal on the list, goats and their by-products, are associated with significant greenhouse gas emissions too.

Swap for: Plant-based protein, chicken, or pork

4. Dairy milk

Dairy is also climate-intensive since it comes from cattle. There are plenty of alternate milks to choose from these days, and while they all require different amounts of land and water to grow, Bergen says they are almost always more sustainable than dairy milk.

Swap for: Non-dairy milk

5. Cheese, butter, and yogurt

Also by-products of cows and ruminant animals, cheese, butter, and yogurt are not the most sustainable options.

Swap for: Cashew “cheese,” tahini, plant-based yogurts

6. Seafood

Though it depends on where it was caught and raised, some types of fish that often make the list include shrimp, tuna, and Chilean sea bass (toothfish).

Swap for: The smaller fish (mackerel, anchovies, sardines, herring)

7. Bottled Water And Soft Drinks

While not nearly as resource-intensive as red meat, Rose notes that many beverages have a higher footprint than you might expect. This is in part because they come with lots of packaging and tend to be pretty heavy to ship. It also takes a lot of raw material to make these drinks. “Say you make a glass of orange juice. It takes a lot of oranges to do that. And then most of what’s left over gets thrown away. It’s the same with wine and beer,” he explains. “There’s a lot of processing that’s going on to get to that output.”

Swap for: Filtered water from the tap

8. Delicate out-of-season fruit

While blueberries and raspberries do make for a sweet treat in winter, Rose notes that they will not be the most sustainable option. More often than not, these fragile fruits were shipped to you from somewhere else on an airplane—and have the carbon emissions to prove it. “They’re particularly bad if they were grown in a greenhouse because then you have the impacts from that and the air travel,” he explains. “That’s a big price on the environment too.”

Swap for: Seasonal fruits or preserved jams

9. Palm oil

Palm oil plantations are a major driver of deforestation around the world, particularly in Southeast Asia. The cheap oil can be hard to avoid (beyond just food, it’s in tons of personal care products), so look for RSPO-certified deforestation-free palm when you can.

Swap for: RSPO-certified palm oil

10. Table sugar

Like palm oil, table sugar (sucrose) is a cheap crop that’s now being grown in areas of high biodiversity. (It’s also pretty water-intensive to cultivate.) Swap it for other natural sweeteners that don’t have the same land-use concerns.

Swap for: Honey or maple syrup

Tips To Follow A Sustainable Diet

Beyond making these sustainable swaps, here are a few more ways experts recommend reducing the overall impact of your diet:

1. Use meat as a flavouring rather than the main dish

“The American idea is that you have the main protein item as the centre of your plate, but in a lot of cultures, the meat or fish is used in a sauce,” Rose notes. Take a cue from this eating philosophy and think of meat as less of a centrepiece and more of a side dish for your vege, grains, and plant proteins.

2. Reduce your food waste

“Another part of eating sustainably is to reduce the amount of food you’re wasting,” says Bergen, because that’s just energy and resources you’re throwing in the bin.

According to one 2014 analysis, food loss makes up a whopping 28% of the overall carbon footprint of the average U.S. diet each year; equivalent to the emissions of 33 million cars.

“We all throw out too much food,” Rose says, but you can keep waste to a minimum by planning your meals ahead of time, only buying what you need, and getting creative with your scraps.

3. Start composting

Compost any food scraps you do have so that they funnel back into the earth instead of decaying in a landfill (another source of planet-warming methane). Join a composting program in your community or start a bin at home using this guide.

4. Avoid packaging

Reynolds says that avoiding food that comes in plastic packaging is another way to reduce the environmental impact of your diet, though she notes that isn’t feasible for everyone. But if you do have the time and resources to shop for loose produce, get your grains from the bulk bin, or make your own package-free nut milk.

“A caution, however, is that making these types of changes is not a stand-in for systems-level and policy changes that can support more sustainable and equitable food systems,” Reynolds adds, bringing us to the final point.

5. Advocate for system-level change in your area

Encourage your local government or school board to purchase healthy and sustainably grown food for children.

“Readers can take steps to learn about food policies where they live and support policymakers who are making well-informed and community-driven food policy a priority,” Reynolds adds.

The Bottom Line

Food systems are super complex, but consider this guide an appetizer in your journey to find a sustainable diet that works for you, and advocate for a food system that supports your community.