According to National Geographic, studies show that the skins of certain fruits and vegetables contain many antibacterial compounds and chemicals that combat diabetes, inflammation, and cancer.
Here are some of the most nutritious options:
Apples
When it comes to apples, “the skin is the most nutrient-dense part” – Joan Salge Blake, a nutrition professor at Boston University, notes. “The skin of an apple contains over 300% more vitamin K, over 140% more vitamin A, and over 110% more vitamin C.”
Apple skins are also rich in both soluble and insoluble fiber and quercetin (a powerful antioxidant) – says Bazilian, author of the series “Eat Clean, Stay Lean.” “You will chew more if you eat the skin, which slows down your eating pace.”
So, don’t bother peeling apples, whether you eat them raw, cooked, or baked. For a delicious snack or dessert, bake the whole apple in the oven or peel and bake strips with a bit of cinnamon.
The skins of certain fruits and vegetables contain many antibacterial compounds. (Photo: National Geographic).
Carrots
Research has shown that the skin of a fresh carrot makes up only 11% of its weight but contains 54% of phenolic acid – which acts as an antioxidant. Carotenoids, vitamin K, niacin, and vitamin C are also more concentrated in the skin than in the carrot’s interior.
Simply wash the carrots and eat them raw or cooked. Jackie Newgent, a nutritionist and chef specializing in vegetables in New York, suggests you can peel them into strips and fry for a crispy snack; or use the “carrot skin strips” in salads.
Citrus Fruits
The skins of oranges, grapefruits, and lemons not only contain more vitamin C and carotenoids than the pulp but are also rich in hesperidin – a powerful antioxidant with anti-inflammatory properties that may help regulate blood sugar levels.
Studies have found that people in Arizona who regularly consume citrus peels have a 34% lower risk of developing squamous cell carcinoma of the skin. Another study showed that citrus peels may have neuroprotective effects, improving cognitive function in older adults.
Additionally, research published in the journal Molecules in 2023 found that compounds in lemon peels have various anti-cancer effects on liver cancer cells.
You can zest citrus peels into salads, soups, casseroles, or baked goods; or use them to season rice, chicken, fish, or roasted or stir-fried vegetables.
Eggplants
The deep purple skin of eggplants shows that they are rich in beneficial antioxidants. Specifically, the skin of eggplants contains nasunin – a compound that protects cell membranes in the body and brain. Additionally, Salge Blake notes that “nasunin reduces inflammation in the body and LDL cholesterol.”
When preparing dishes with eggplants, just keep the skin on as you cook. For a special dish, Newgent suggests mixing strips of eggplant skin with olive oil and spices, then roasting them to create a faux “bacon.”
Kiwi
Many people are unaware that kiwi skin is edible and healthy.
“Kiwi skin contains twice the amount of fiber compared to the inside” – Alexandra Kazaks, a research advisor in health and nutrition science at the Institute of Food Technology, states. The fuzzy skin also contains more folate and vitamin E than the “flesh.”
Some experts recommend washing the kiwi and eating it whole or slicing it with the skin on. Salge Blake mentions: “When sliced, you will consume more of the kiwi’s ‘flesh’ than the skin.” You can toss those kiwi slices into a fruit salad or green salad or throw them into a blender for a smoothie.
Remember: “If you have a history of kidney stones, you should avoid eating kiwi skin as it contains high levels of oxalate” – Young, author of “Finally Full, Finally Slim,” warns.
Mango
People often don’t think about eating the whole mango skin – but you should.
The vibrant mango skin is not only edible but also rich in vitamin C, carotenoids, fiber, and other antioxidants. It is also “a good source of pectin – a soluble fiber that helps lower cholesterol levels and slows gastric emptying, making you feel fuller for longer” – Salge Blake states.
Research shows that eating mango skin can reduce fat accumulation in individuals. And many different bioactive compounds – including phenolic acid, mangiferin, and beta-carotene – found in mango skin are recognized for their antibacterial, anti-diabetic, anti-inflammatory, and anti-cancer properties.
Research shows that eating mango skin can reduce fat accumulation. (Photo: Internet).
You can cut mango into pieces and eat the skin or use it in cooking.
“Because mango skin can be a bit bitter, I recommend sautéing the mango skin with some sweet mango flesh to balance the flavors” – Newgent, author of “The Plant-Based Diabetes Cookbook,” suggests.
Potatoes
Potato skins are often not considered healthy food as they are a staple in bar menus, often “slathered with all sorts of fats” – Keith Ayoob, a nutritionist at Albert Einstein College of Medicine in The Bronx, says. “But that’s not necessarily the case.”
Potato skins are not only rich in vitamin C, iron, potassium, and several B vitamins, but “50% of the fiber in potatoes is found in the skin” – Salge Blake notes. So, forget about peeling potatoes or sweet potatoes: Just scrub the skin under running water, then cook and eat with the remaining “flesh.”
Alternatively, you can scoop out the “flesh” of the potato and eat the baked skin topped with sautéed onions and mushrooms (or other vegetables). Newgent also suggests sautéing chopped potato skins with herbs to “garnish” other dishes.
Tomatoes
Speaking of wasting time and nutrients: “Some people peel tomatoes when making soup or sauce, but there’s no need to do so” – Salge Blake states. “Peeling means you could lose up to 80% of the lycopene – a compound that fights cancer.”
The skin also contains slightly higher concentrations of vitamin C and some B vitamins than the “flesh.” Studies have shown that peeling reduces the overall antioxidant activity of tomatoes.
Your solution is to use the whole tomato. “Sometimes, cooking is much easier when you don’t have to peel these things” – Ayoob says.
