How to Eat a More Sustainable Diet

Small changes can make a big difference: Research-backed, practical ideas for environmentally friendly eating from the Friedman School of Nutrition Science and Policy

This article originally appeared in the Tufts Health & Nutrition Letter, published each month by the Friedman School of Nutrition Science and Policy. Find out how to get expert guidance on healthy cooking, eating, and living.

The food choices you make can have a real impact on the environment. Growing crops and raising animals for food creates about a quarter of the world’s greenhouse gas emissions and accounts for about 70 percent of all freshwater use the vast majority of tropical deforestation. On top of that, food waste and packaging have their own environmental impacts. Fortunately, there are specific simple things you can do to make a difference. Take a look at the ideas below and choose a few that might work for you.

Eat Less

“As a population here in the U.S., we eat too much,” says Timothy Griffin, PhD, a professor in Nutrition, Agriculture and Sustainable Food Systems at the Friedman School. “If we could cut back on overeating, it would be good for the environment, and for our health!” Try serving yourself smaller portions and waiting to see if you’re truly hungry before taking seconds. Other strategies include eating off a smaller plate, eating without distractions, chewing your food well, putting your fork down between bites or every few bites, sharing with someone, and packing some food up for the next day.

Cut Food Waste

“One-third or more of food is thrown away in U.S.,” says Griffin, “and much of this waste is at the household level.” Not only are we throwing away money, we are wasting the water used to grow that food, the oil used to deliver it, and other natural resources that go into creating food and getting it to your table. Meanwhile, food packaging clogs our oceans and dumps, and food rotting in landfills contributes to global warming. Try these tips to cut your food waste:

  • Plan meals. Base your shopping list on only what you plan to use.
  • Be realistic. That jumbo bag or box may cost less, but you’re throwing away your money (while harming the environment) if it goes bad before you finish it.
  • Store food properly. Learn how to store perishable foods so they stay fresh; seal bags and packages tightly to keep breads, rolls, and crackers from getting stale; wrap foods to be frozen tightly with as little exposure to air as possible to reduce freezer burn; keep oils away from light and heat to prevent them from getting rancid; and keep milk cold to prevent early spoilage.
  • Freeze extra. Not going to use the entire package of chicken breasts? Freeze some for another day. Bread, veggies, and fruits can be frozen as well (or pickled or preserved).
  • Choose wisely. Fresh vegetables are great for a salad or a crudité platter, but bags of frozen vegetables have a longer shelf life and great for stir fries, soups and stews.
  • Have “Leftover Day.” Pick one day a week to use up whatever is in your fridge. Have a buffet of bits and pieces from previous meals; make a stir-fry with those extra veggies and proteins; top a grain bowl or green salad.
  • Be creative. Think outside the box when it comes to finding ways to use up food before it goes bad.
  • Donate. Help your community by dropping unopened extras that you are unlikely to use at your local food pantry. Made more of a dish than you can reasonably eat? Offer to drop some at a neighbor’s door or invite a friend to join you.
  • Use your sense and senses. Foods are good for several days past their “Sell by” dates and are almost always good beyond their expiration or “Use by” dates. Trust your senses more than the dates. Look for mold, off odors, colors, or tastes, and unexpected carbonation or package swelling.
  • Repurpose. Make stale bread into croutons or breadcrumbs. Cook edible stems (like beet tops) instead of discarding them. Turn wilting veggies and fruits into soup (see recipe on page 7) or smoothies. Cook mold-free, mushy berries into oatmeal or puree into a sauce (try it stirred into plain yogurt!). Slice and freeze soft bananas and whip into a smooth ice-cream substitute in a blender or food processor.
Compost bin in backyard

Return fruit and veggies scraps to the earth with a compost bin in your yard. Photo: Skorzewiak / Shutterstock


When all else fails, return fruit and veggies scraps to the earth. Start a compost bin in your own yard or look for local compost centers or farmers who will take those scraps off your hands.

Make Smart Swaps

Some foods have a bigger environmental impact than others, so cutting back on these in favor of other healthy foods you enjoy is a great way to have an impact. “Food that comes from animals has a bigger environmental impact than plant foods,” says Griffin. “Beef gets the most attention, because raising cattle requires a lot of land, most of which is pasture or grazing land, and the animals emit methane. The same is true for dairy animals, but in that case the food (milk) comes from the animal rather than from the slaughter of the animal, and the cattle live longer. Other meats (pork and poultry) come next in terms of environmental impact, followed by fish and seafood.” Replacing animal proteins with plant proteins—soy and other legumes, nuts/seeds, and whole grains (particularly higher-protein grains like quinoa and amaranth)—would have the biggest environmental benefit. “Keep in mind that foods like plant-based meat substitutes and non-dairy milks, yogurts, and cheeses have a smaller environmental impact than the animal versions,” Griffin says, “but these are also ultraprocessed foods, so there’s a tradeoff there.”

Changes do not have to be big to make a difference. A new study looked at how making slight changes to your diet would impact your water scarcity footprint and greenhouse gas emission levels. The researchers analyzed the environmental impact of participants’ reported dietary intake, and then recalculated after swapping out specific food items for nutritionally and calorically equivalent options that were more climate friendly. Not surprisingly, swapping out beef had the biggest impact. Had the participants chosen poultry or pork instead of beef, their average carbon footprint would have decreased by over 48 percent and water scarcity footprint would have gone down around 30 percent. Other environmentally impactful swaps included choosing peanuts instead of almonds, swapping cod in for shrimp, and subbing soymilk for cow’s milk.

Woman in a tan dress shopping for leafy vegetables at a farmer's market

Perhaps your area has farmers markets or farm stands, or you can buy a share from a grower who participates in Community Supported Agriculture (CSA). Photo: / Shutterstock

Buy Local

Patronizing shops in your neighborhood supports the local economy, and buying food grown as locally as possible (when it’s in season) cuts back on the air pollution created by shipping the food to your area. “Buying local also allows people to engage with the food system,” says Griffin. “Going to a farmers market, for example, allows you to talk to the person who made what you’re eating. It connects you to your food.”

While it is of course necessary to buy imported produce and take advantage of frozen options in areas with short growing seasons and/or limited selection, buying seasonal foods grown as locally as possible is a positive step if you have the option. Perhaps your area has farmers markets or farm stands, or you can buy a share from a grower who participates in Community Supported Agriculture (CSA). This would provide you with a box of locally grown produce each week. You could also grow your own! Herbs and a number of veggies, including tomatoes, peppers, and green onions (scallions), do very well in containers, so you don’t need a yard if you’d like to supplement your fruit and veggie selections with home grown.

Reduce, Reuse, Recycle 

Packaged foods create a massive amount of waste, much of which is difficult or impossible to recycle. Plastic is filling landfills and clogging our oceans. Try the following tips to cut down on your waste.

  • Carry a reusable water bottle, or refill plastic water bottles rather than tossing after first use.
  • Ask your coffee shop to refill your reusable cup instead of giving you a new paper cup each day.
  • Buy your produce unbagged and unwrapped. (Reusable produce bags are a good solution if you prefer to bag).
  • Buy fewer prepared foods and packaged products (this is good for your diet as well as the environment).
  • Consider glass bottles and jars instead of plastic if they are available, then wash and reuse. (Jars are great for storing leftovers, keeping the broth you make from your scraps, or pickling those veggies that might go to waste.)
  • Take full advantage of recycling programs in your area.

“Incremental changes are fine!” says Griffin. “Think consciously about what environmentally friendly changes—big or small—would be appropriate for you.”

vegetables in the store

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This article originally appeared in the Tufts Health & Nutrition Letter, published each month by the Friedman School of Nutrition Science and Policy. Find out how to get expert guidance on healthy cooking, eating, and living.

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