You will probably throw these food scraps away. This is why eating it is good for you and the environment.

According to the United States Department of Agriculture (USDA), between 30% and 40% of America’s food supply is lost – literally thrown away – every year. Some parts of food that we assume to be waste are not only edible, but also nutritious. From peels to stems, peels and more, sometimes what we think of as leftovers are actually just as nutrient-rich as the parts we normally eat. If Earth Day has the environment in mind, using it 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 need to know.

Eat the peels

“I think it’s kind of amazing that people peel things,” PK Newby, food scientist and founder of Food Matters Media, tells Yahoo Life. She says the skins of many fruits and vegetables – including carrots, apples, potatoes, eggplant and sweet potatoes – are perfectly edible and “where you get so much of the nutritional value.”

Newby notes that many peels are rich in fiber, vitamins and minerals. They’re also where fruits and vegetables, including nuts, store their protective phytochemicals, which are part of a plant’s immune system and provide similar effects to people who eat them, according to the University of California, Los Angeles (UCLA). Phytochemicals help prevent cell damage, meaning they even protect against the development of cancer.

As a rule of thumb, “Whatever the plant does for itself, it will do for you,” Newby says when you eat it. “Eggplant, for example, is a great vegetable with a higher fiber content and its rich purple color is bursting with something called nasunin, a powerful plant chemical, and you only get that in the skin,” she explains. Nasunine has anti-cancer properties, helps prevent damage to brain cells and slows the signs of aging. “Plants have beautiful bright colors, partly to attract or repel pests or other species, so the same benefit goes to the person who eats them.”

Likewise, the skin of an apple is the most nutrient-dense part of the fruit. An unpeeled apple has higher amounts of vitamins A, C and K compared to those in a peeled apple, and is also richer in calcium and potassium, according to the USDA. The statistics are similar for an unpeeled potato, which contains more vitamin C, potassium, folic acid, magnesium and phosphate than a peeled potato, according to the USDA.

If you’re concerned about pesticides, don’t worry too much, Newby says. “The health benefits of the peels outweigh the risks of the pesticides,” she says. While removing 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 products is quite minimal, according to the Environmental Protection Agency (EPA). Most pesticide residues – which are highly regulated – are removed simply by washing your produce. Concerns about pesticides on peels are often “misplaced,” Newby says. “They miss the forest for the trees.”

Boil 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 food dollars and get more nutritional value and less food waste,” she says.

Not only do you get more nutrients when you consume a whole fruit or vegetable, you also get more diverse nutrients. “The leaves and roots of the same plant species will differ in nutritional value,” says Newby. Because plants grow from their roots, they store energy in carbohydrates in both starch and sugar forms, Newby explains. However, the leaves are responsible for photosynthesis, which is made possible by a host of vitamins and minerals, including potassium, calcium, phosphorus, magnesium and zinc, according to the Smithsonian Environmental Research Center, along 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. In addition, most leafy vegetables also contain a good dose of fiber.

She is especially fond of roasting beets, unpeeled, along with their leaves. You can also use the whole root, but because the green can be a bit bitter, Newby suggests making a pesto from it (she likes to say, “You can make that pesto” about lots of greens that you might not immediately find appealing ). or your family).

Make a nutritious broth from it

If you’re not sure you can eat a leftover food right away, you can probably still use it to make a hearty, nutritious vegetable stock, Newby advises. She keeps a bag in her freezer to collect scraps such as parsley stems, carrot tops and the ends of celery sticks, potatoes and parsnips over time. You can even save and use otherwise inedible parts of fruits and vegetables, such as onion peels.

“Quercetin, a powerful antioxidant, is mainly found in the outer layer of the onion skin,” explains Newby. Not only is quercetin an antioxidant — meaning it fights cell damage from free radicals — it is also anti-inflammatory and antiviral and has properties that may help protect against diabetes, heart disease, cancer and neurodegenerative diseases, according to the Icahn School of Medicine at Mount Sinai.

Instead of eating raw onion skins, which are difficult to digest and can cause digestive problems, Newby suggests tossing them into a vegetable stock or tomato sauce along with other saved leftovers. They’re eventually strained out of the broth, but “you get all those nutrients, and you have a beautiful broth that’s salt-free, and you’ve used up all that stuff.”

While you replenish your supply with nutritious leftovers, you also prevent food from going to waste, like 45% of fruits and vegetables worldwide. Newby advocates composting any food you can’t use, but she recognizes that many people may not have access to composting or collection locations. “Composting is really an afterthought,” says Newby, who instead focuses on using the food she buys as much as possible. “I create so little waste and not much compost; You’re not throwing things away, you’re reducing what’s thrown away,” whether it’s in the trash or the compost bin, by using every part of your products, Newby says.