Why You May Want to Keep Fruit and Vegetable Peels

New research indicates that the skins, seeds, and stalks people often throw away can hold more fiber than the parts we usually eat.

Before tossing fruit peels, vegetable skins, or seeds into the trash, it may be worth taking a second look.

Researchers say the parts of produce most of us discard can contain far more dietary fiber than the portions that end up on our plates. From watermelon rind to butternut squash skin, those overlooked scraps could help raise fiber intake while also cutting down on food waste.

“We’re often looking for the next superfood or supplement to improve our health, when part of the answer is already sitting in the kitchen, about to be thrown in the trash,” says Laurel Santiago, a licensed dietitian nutritionist and the owner of Integrative Center for Nutrition in New York City, who was not involved in the study.

Discarded Produce Parts Can Be Surprisingly High in Fiber

In the study, researchers at King’s College London examined 12 widely eaten fruits and vegetables, including pineapple, watermelon, butternut squash, broccoli, and bell peppers.

They compared the fiber in commonly discarded parts, such as peels, skins, seeds, and stalks, with the fiber in the portions people usually consume. In 10 of the 12 foods studied, the discarded parts contained more fiber.

Some of the clearest examples included the following:

• Watermelon rind: 2.1 grams (g) of fiber per 100 g, about the same as a slice of whole-wheat bread
• Butternut squash skin and seeds: 9.25 g of fiber per 100 g
• Pineapple skin and core: together contained about 5.5 times as much fiber as the fruit’s flesh
• Broccoli stalks: contained about 28 percent less fiber than the florets, making them an exception to the overall pattern

Earlier research has already suggested that peels and other typically discarded produce parts can be good sources of fiber, antioxidants, and other beneficial plant compounds. This new study adds to that evidence by directly comparing the discarded and commonly eaten portions of certain foods.

“This concept is not new; many chefs and home cooks do this already,” says the study author Rachel Gibson, PhD, a reader in nutrition and dietetics at King’s College London. “Our approach was to look at the potential health benefits — as we know that consumers are more switched on by health than sustainability messaging.”

Ways to Use Fruit and Vegetable Parts You Normally Throw Out

You do not need to start eating tough or unappealing peels to make better use of produce.

“There are easy, appealing ways to eat some of the discarded fruit and veggie parts,” says Jennie Miremadi, an integrative clinical licensed dietitian nutritionist in Los Angeles specializing in digestive health.

Experts recommend beginning with parts that are already known to be edible and simple to prepare. Examples include:

• Watermelon rind: Rather than discarding the whole rind, use the white layer between the pink flesh and the hard green outer skin. “Throw the white part of the watermelon rind (pith) into a stir-fry or ferment it and turn it into pickles,” Miremadi says.
• Pineapple skin and core: The firm core can be blended into smoothies or mixed with coconut milk to create a curry base, Miremadi says. Pineapple skins can also be boiled with ginger and honey for tea, though she advises against eating the tough outer skin directly.
• Butternut squash skin and seeds: Instead of peeling the squash, try roasting it with the skin on. “When roasted, the skin softens and can be eaten as part of the dish,” Gibson says. “This is probably one of the easiest ‘Root-to-Tip’ practices for consumers to adopt — and much easier than peeling a squash!” Miremadi also suggests roasting the seeds with sea salt and extra-virgin olive oil.
• Bell pepper seeds and pith: The seeds and white membranes can be added to soups, sauces, and other cooked dishes. Santiago says to use the seeds sparingly if their slightly bitter flavor is unpleasant.
• Broccoli stalks and other peels: Even though broccoli stalks have less fiber than the florets, they are still edible and can be sliced into stir-fries, grated into salads, or blended into soups, Gibson says. She also suggests roasting cauliflower leaves or adding them to curries.

Why Fiber Matters for Health

Fiber is important for digestive health, but its benefits go well beyond the gut.

“Fiber does so much more than keep [bowel movements] regular,” Santiago says. “It feeds gut bacteria, steadies blood sugar, supports healthy cholesterol, and helps regulate appetite.”

Even so, many adults in the United States do not get enough of it.

Women ages 19 to 50 generally need about 25 g of fiber a day, while men in the same age group should aim for about 38 g.

Miremadi recommends increasing fiber slowly and drinking enough water to help avoid digestive discomfort as the body adjusts.

“One of the biggest mistakes I see people make when trying to increase fiber in their diet is adding in way too much fiber too quickly,” Miremadi says. “When you drastically increase the amount of fiber in your diet too rapidly, it can lead to bloating, gas, or other digestive discomfort.”

Anyone with a digestive condition that requires dietary restrictions should check with a healthcare team before making major changes to fiber intake.

Is It Safe to Eat Peels and Rinds?

While many discarded produce parts are edible, the researchers say more evidence is still needed on the safety of eating some unfamiliar peels and rinds.

In focus groups conducted for the study, food safety concerns were a major reason people hesitated to eat these parts, while possible health benefits encouraged them to consider it.

Gibson says the next stage of research will examine the safety of eating peels and rinds more broadly, with the aim of offering clearer guidance for consumers and food service professionals.

“Wider adoption will require robust evidence on nutrition, safety, acceptability, and practical implementation, which is exactly what our ongoing research aims to provide,” she says.

For now, experts advise choosing produce parts already known to be safe to eat and following proper food-handling steps, including washing fruits and vegetables thoroughly under running water before cutting or peeling them, even if the skin will not be eaten. A vegetable brush can help clean firm produce such as squash or watermelon.

And increasing fiber does not have to mean eating every peel or rind.

“You don’t need a dramatic overhaul,” Santiago says. “Chia seeds at breakfast, beans in your soup, whole fruit instead of juice. Small swaps, repeated daily, can add up faster than any single superfood.”