Did you realize that when you peel and discard the skins of fruits and vegetables, you’re actually removing one of the most nutrient-rich parts of the plant? If you want to really maximize your dietary intake of valuable antioxidants, vitamins, and minerals, you should be eating the skins, too!
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The skin or peels of fruits and vegetables are jam-packed with beneficial nutrients, dietary fiber, and protective antioxidants that are needed for good health and disease prevention. Unpeeled fruits and vegetables contain significantly higher levels of these nutrients compared to when they’re peeled. For example, when you peel an apple, you’re throwing away half of the apple’s beneficial fiber content. Enjoying an apple with the skin on will also provide you with 31% more vitamin C, 60% more vitamin A, and a whooping 300% more vitamin K than a peeled apple (1).
WHICH SKINS ARE EDIBLE
Most fruit and vegetable skins are edible and can be easily incorporated into meals. Potatoes (only avoid eating them if the skin is green), yams and sweet potatoes, squash, beetroot, bell peppers, parsnips, eggplants, cucumbers, carrots, apples, berries, citrus fruits (cooked or zested), cherries, kiwi, apricots, grapes, peaches, pears, and plums, all have edible skins.
However, some fruit and vegetable peels are tough and difficult to digest, even when they’re cooked. These inedible peels should be removed and put in the compost. These include melons, pineapples, lychee, papayas, mangos, and banana peels. While onion and garlic skins are also inedible, they make a great addition to stocks. Avocado skins are also considered inedible, but when you’re peeling off an avocado skin, make sure you don’t excise the healthy dark flesh that’s just under the skin—this part is loaded with beta-carotene, antioxidants, and vitamins B12 and E. While mango skins aren’t considered dangerous to eat, their skins can be bitter, and they contain a toxin called urushiol (the same compound found in poison ivy) that can cause inflammation and digestive issues.
FIBER
Fruit and vegetable skins are an especially good source of insoluble and soluble fiber. On average, around one third of the fiber content in fruit and vegetables can be found in their skin (2). This extra fiber from the skin will make you feel full for longer after eating and slows down the absorption of glucose from your meal. This in turn helps keep blood sugar levels balanced. Eating more fiber will also help lower cholesterol levels and supports digestive health by preventing constipation and boosting gut microbiota. Fiber is considered a prebiotic food as it’s fermented by bacteria in the gut. This produces short-chain fatty acids that feed beneficial gut microbiota and help stimulate their growth.
ANTIOXIDANTS
Antioxidants are a vital part of everyone’s diet as they neutralize free radicals that cause oxidative stress to the body. A build-up of free radicals increases the risk of chronic diseases like cancer, cardiovascular disease, type-2 diabetes, Alzheimer’s, and premature ageing.
Fruits and vegetables are naturally high in beneficial antioxidants, especially purple, blue, red, orange, and green leafy varieties. The more colorful the fruit or vegetable, the more antioxidants they usually contain. In most cases, the colorful skins have concentrated levels of these protective antioxidants and studies have shown that antioxidant levels can be up to 328 times higher in fruit and vegetable peels compared to their pulps (3).
PROPERLY CLEANING PEELS & WHY YOU SHOULD BUY ORGANIC PRODUCE
You should always wash non-organic fruits and vegetables well, especially when you’re consuming their skins. Pesticides and insecticides are routinely sprayed on commercially grown crops and residues of these toxic chemicals are found on the skins—and even in the flesh—of fruits and vegetables. Soft-skinned fruits readily absorb pesticides so these toxins can easily penetrate the skin. This is why it’s important to choose organic soft-skinned fruits such as berries, plums, grapes, apricots, and peaches.
For harder-skinned produce, washing and scrubbing is a good way to remove some of the pesticide residue. It has been reported that 41% of pesticide residue is removed from washing alone. However, soaking fruits and vegetables in a baking soda solution for two minutes will remove more pesticides than rinsing under tap water for two minutes. (Use one teaspoon of baking soda to two cups of water.)
Another reason you need to wash and scrub non-organic produce well is that some fruit and vegetables have been covered with a protective layer of wax. This is used to give produce an appealing shine and it also keeps them firm and plump. Wax also delays ripening so produce can last for weeks to months after being picked.
Commonly waxed produce includes apples, bell peppers, cucumbers, egg plants, citrus fruits, parsnips, pumpkins, sweet potatoes, turnips, and tomatoes.
Produce wax is usually made from the leaves of Brazilian palm trees, beeswax, shellac, mineral oil, and petroleum jelly and it sometimes contains fungicides to help prevent mold.
Some fruits like grapes, berries, apples, and plums naturally produce their own wax, which looks like a fine white dust, and rinsing easily removes this type of natural wax.
When you buy produce directly from farmers at grower’s markets, produce is much less likely to have been artificially waxed.
If you are concerned about exposure to pesticides, buying organic is your best option. Buying organic produce is the ideal way to avoid exposure to pesticides and other chemicals sprayed on crops.
COOKING HACKS FOR FRUIT AND VEGETABLE PEELS
Don’t let your fruit and vegetable peels go to waste! Instead of throwing out the skins, use them to give your meals a nutritious boost. Not only is eating the peels better for your health, it also helps reduce the impact of your food waste, too. Here are some delicious and practical ways to liven up your meals with fruit and vegetable skins.
CITRUS PEELS
Citrus zest is extremely versatile, adding extra flavor and increased nutrient value to a variety of sweet and savory dishes. You can zest the skins of lemons, limes, grapefruits, and oranges using a microplane, zester, or grater, but stop when you hit the white part of the skin.
Compared to the juice and pulp, citrus peels are also a more concentrated source of vitamin C, fiber and active compounds like d-limonene. D-limonene is responsible for many of lemon’s health benefits including its ability to fight several types of cancer (4) and lower blood sugar and cholesterol levels.
Lemon and lime zest are delicious sprinkled over roasted root vegetables, stir-fries, rice dishes, and salads. Use citrus zest in cakes and muffins, and to decorate baked goods and raw desserts. Try orange zest on ricotta toast or in scones, carrot cake, and fruit loaves.
Try dehydrating citrus zest in a low-temperature oven or in a dehydrator until crisp and dry. Dried lemon zest is ideal to grind up in a mortar and pestle with herbs for tasty rubs and seasoning for meat, chicken, and fish.
Add some lemon peels to your olive oil bottle for a lemon-infused oil for salads.
Put leftover citrus peels in a container in the freezer to use for drinks, and use citrus peels in cocktails and iced teas. A study has shown that people who drink strong, hot black tea with lemon peel had a significantly reduce risk (70% less) of developing skin cancer (skin squamous cell carcinoma) compared with those who didn’t (5).
Preserved whole lemons are delicious added to Moroccan dishes with fish, lamb, chickpeas, and chicken.
Enjoy oven-baked chicken and fish topped with slices of unpeeled lemon or try placing slices of lemon in between chicken and fish kebabs.
OTHER FRUIT PEELS
Fruit is the perfect fiber-rich snack or healthy addition to your breakfast. Don’t miss out on all those extra nutrients—eat fruit with their skins on!
Give your next berry smoothie a fiber-boost by adding leftover apple peels. Apple peels are also an excellent source of quercetin which is a nutrient that has impressive antioxidant and anti-inflammatory properties. Scientists have also discovered a group of active compounds called triterpenoids found in the skins of apples that may help fight a number of different types of cancer (6).
Keep the skins on fruits when you add them to cakes, muffins, fruit crumbles, and other baked goods.
Stewed peaches, plums, apples, pears, apricots, and nectarines added to yogurt or eaten with natural muesli are a delicious way to incorporate fruit skins into meals.
Add shredded unpeeled apples or pears to Bircher, natural muesli, or natural yogurt for a delicious and healthy breakfast or snack.
VEGETABLE PEELS
Keep leftover vegetable peels and use them to make a vegetable stock for gravies, soups, risotto, sauces, and broths. Simmer vegetable peels (carrots, parsnips, potato, sweet potato, onion, and garlic) with some herbs for 40 minutes, then strain. Try storing leftover peels in a container in the freezer until you have enough to make a stock.
Leave the skins on root vegetables when roasting them in the oven (e.g. potato, sweet potato, carrots, yam, beetroot, and parsnip). Make sweet potato and potato wedges with the skins on or try making crispy chips out of roasted vegetable peels. (Toss the peels in some olive oil and sea salt and lay them out on a baking tray. Bake your peels in a 400*F oven for around 10 minutes or until crispy, tossing halfway.) Veggie peel chips are delicious served with tzatziki, hummus, or added to burgers or tossed through salads.
More Info:
References:
(1) SELF Nutrition Data, know what you eat. www.nutritiondata.self.com.
(2) Alvi Shahnaz, M. Masud Kamal Khan et.al. Effect of peeling and cooking on nutrients in vegetables. Pakistan Journal of Nutrition 2(3), March 2003.
(3) Changjiang Guo, Jijun Yang et. al. Antioxidant activities of peel, pulp and see fractions of common fruits as determined by FRAP assay. Nutrition Research, Vol 23, Issue 12, Dec 2003, pg. 1719-1726.
(4) Xiao-Guang Lu et al. Inhibition of growth and metastasis of human gastric cancer implanted in nude mice by d-limonene. World J Gastroenterol. 2004 Jul 15;10(14):2140-2144.
(5) Hakim IA, Harris RB, Weisgerber U. Tea intake and skin squamous cell carcinoma: influence of type of tea beverages. Cancer Epidemiology, Biomarkers and Prevention. 2000;9:727–731.
(6) Cornell University. An apple peel a day might keep cancer at bay. Science Daily, June 3, 2007.