Between 30% and 40% of America’s food supply goes in the trash – is literally thrown away – each year, according to the USDDepartment of Agriculture (USDA). Some of the parts of food that we assume are junk are not only edible but also nutritious. From peels to stems to rinds and more, sometimes what we assume are leftovers are actually as nutrient-dense or more nutrient-dense than the parts we normally eat. If Earth Day has the environment in mind, using them will benefit you and help reduce the amount of methane – one of the most harmful greenhouse gases – released into the air by food rotting in landfills.
Here’s what you should know.
Eat the peels
“It’s amazing to me that people peel things off,” PK Newbie, nutritional scientist and founder of Food Matters Media, told Yahoo Life. She says the peels of many fruits and vegetables — including carrots, apples, potatoes, eggplants and sweet potatoes — are perfectly edible and are “where you get a lot of the nutritional value.”
Newby notes that many peels are rich in fiber, vitamins and minerals. They’re also where vegetables and fruits, including nuts, store their protective phytochemicals, which are part of a plant’s immune system and provide similar effects to humans who eat them, according to the University of California, Los Angeles (UCLA). Phytochemicals help prevent cellular damage, which means they even protect against the development of cancer.
As a general rule, “whatever the plant does for itself, it will do for you” when you eat it, says Newby. For example, “eggplant is a great vegetable with high fiber content and its rich purple color is full of what’s called nasunin, which is a powerful plant chemical, and you’ll only get that on your skin,” she explains. Nasunin has anti-cancer properties and helps prevent damage to brain cells and slows the signs of aging. “Plants have beautiful bright colors, in part, to attract or ward off pests or different species, so the same benefit goes to whoever eats them.”
Likewise, the skin of an apple is the most nutritious part of the fruit. One apple with peel has higher amounts of vitamins A, C and K compared to those in a peeled apple, and is also higher in calcium and potassium, according to the USDA. The statistics are similar for a potato with skinwhich contains more vitamin C, potassium, folate, magnesium and phosphate than a peeled one does, according to the USDA.
If you’re worried about pesticides, don’t worry too much, says Newby. “The health benefits of the peels outweigh the risk of pesticides,” she says. While eliminating pesticides from the environment is important to prevent contamination of water, soil and animals, the risk to human health from pesticides on the outside of produce is quite minimal, according to the Environmental Protection Agency (EPA). Most pesticide residue – which is strictly regulated – will be removed by simply washing your produce. Concerns about pesticides in the peels are often “misguided,” says Newby. “They are missing the forest for the trees.”
Cook the roots, leaves and stems
“The outer leaves, the stems — the whole cauliflower is edible,” says Newby, adding that you can roast and eat the entire cauliflower or broccoli plant. “That’s where you can save some money on food and get more nutritional value and less food waste,” she says.
Not only do you get more nutrients from consuming a whole fruit or vegetable, but you also get more diverse nutrients. “The leaves and roots of the same plant species will differ in their nutrient content,” says Newby. As plants grow from their roots, this is where they store energy in carbohydrates, both in the form of starch and sugar, explains Newby. The leaves, however, are responsible for photosynthesis, which is made possible by a number of vitamins and minerals, including potassium, calcium, phosphorus, magnesium and zinc, according to the Smithsonian Environmental Research Centeralong with disease-fighting phytochemicals.
“The leaves are often more nutritious than the roots, just because they have a better balance of vitamins and minerals,” says Newby. Plus, there’s also a good dose of fiber in most leafy greens.
She particularly likes roasting beets – unpeeled – along with their leaves. You can also use the whole carrot, but because the greens can be a bit bitter, Newby suggests using them to make a pesto (she likes to say, “You can make this pesto” about many greens that might not be immediately appealing to you or your family).
Turn it into nutritious stock
If you’re not sure you can eat leftovers right away, you can probably still use them to make a healthy, nutritious vegetable broth, advises Newby. She keeps a bag in the freezer to collect scraps like parsley stems, carrot tops and the ends of celery stalks, potatoes and turnips over time. You can even save and use parts of fruits and vegetables that would otherwise be inedible, like onion skins.
“Quercetin, a powerful antioxidant, is mainly located in the outermost layer of the onion skin,” explains Newby. Quercetin is not only an antioxidant — meaning it fights cellular damage caused by free radicals — but it is also anti-inflammatory and antiviral and has properties that may help protect against diabetes, heart disease, cancer and neurodegenerative diseases, according to as Icahn School of Medicine at Mount Sinai.
Instead of eating raw onion skins, which are difficult to digest and can cause digestive issues, Newby suggests tossing them into vegetable broth or tomato sauce along with other saved leftovers. Eventually they will be sieved out of the broth, but “you’re getting all these nutrients and you have a beautiful unsalted broth and you’ve used up all these things.”
By loading your stash with nutritious leftovers, you also avoid food waste, such as 45% fruits and vegetables globally. Newby advocates composting any food you can’t use, but she recognizes that many people may not have access to compost drop-off or pickup locations. “Composting is really after the fact,” says Newby, who instead focuses on using as much of the food he buys as possible. “I create so little trash and compost; you’re not throwing things away, you’re reducing what gets thrown away,” whether in the trash or the compost bin, by using every part of your products, says Newby.
