Nutrients in potatoes and apples are not all in the skin

Everyone has some wise wisdom about nutrition that a parent, grandparent, or other family member taught them as a child. We often take these little pieces of advice or warnings as gospel and never really consider whether they are true, even as we get older.

But some of this food folklore is nothing more than a myth. That’s what a viral post implies about the belief that all the nutrients in potatoes and apples are found in the skin.

Is this just a lie parents tell their kids to make them eat their whole potato or apple, or is there some truth to it?

Are all the nutrients in potatoes and apples in the skin?

No, not all of the nutrients in potatoes and apples are in the skin. Nevertheless, there are many nutrients in the peel.

Fruit and vegetable peels — like that of an apple or a potato — contain a lot of nutrients, but so does the pulp of those foods. Eating the whole potato or apple, including the skin, will give you the most nutrients, but you’ll still have a healthy, nutrient-dense meal if you eat both.

While nutrients are distributed throughout an apple, some nutrients are more pronounced in the peel, while other nutrients are more prominent in the pulp.

The skin contains much of the fiber and flavonoids, which are naturally occurring chemicals with various health benefits, while the meat is reported to contain most of the vitamin C Harvard TH Chan School of Public Health.

This is shown by data from the US Department of Agriculture (USDA). If you eat 100 grams a raw apple with skin, you would get about 2.4 grams of fiber. If you eat 100 grams a raw apple without skinyou would get about 1.3 grams of fiber.

The apple with the skin has 4.6 milligrams of vitamin C, but the apple without the skin still has 4.0 milligrams of vitamin C. You would get about 107 milligrams of potassium in an apple with the skin on, but you would still be getting 90 milligrams of potassium, if you ate your apple without peel. You only lose 1 milligram of calcium and magnesium alike if you choose to peel the apple.

The breakdown of nutrients is similar in potatoes.

The skin of a red potato, a potato commonly used in baking, has Idaho Potato Commission.

“But if you look at potatoes as a whole, you’ll find that most of your potassium and vitamin C is actually in the flesh, not the skin,” said Bwalya Lungu, Ph.D., who teaches food science and food folklore at the University of California Davis.

Not only is the flesh of a potato high in potassium and vitamin C, it is also higher than other foods that are normally considered nutrient dense. For example the Cleveland Clinic says a potato has more potassium than a banana and more vitamin C than an orange.

Potatoes United Statesthe marketing and research organization of the American potato industry, confirms this.

“While the skin contains about half of the total fiber, the majority of the nutrients are found in the potato itself,” says Potatoes USA.

Potatoes USA states that a typical medium-sized potato has 2 grams of fiber with the skin on and 1 gram of fiber without the skin. A typical medium-sized peeled potato contains 620 mg of potassium and 27 mg of vitamin C, but only loses about 150 mg of potassium and 4.5 mg of vitamin C when you remove the potato’s skin.

Still, potato skins aren’t just good for fiber. A Study 2007 by researchers at Oregon State University’s Hermiston Agricultural Research and Extension Center found that vitamin B9, also known as folate, is 30% more concentrated in the skin of a typical potato than in the flesh.

USDA data supports this. That skin alone a salted baked potato has 22 micrograms of folate. The flesh and skin of a salted baked potato together have 28 micrograms of folate.

There’s one situation where keeping the skins on your potatoes makes a big difference in how nutritious your potatoes stay: when you cook them.

Lungu says that cooking potatoes with their skins on minimizes the loss of the potato’s vitamins and minerals that occurs during cooking.

“If you peel them, they lose some of [the potato’s vitamins and potassium]’ said Lungo. “And sometimes those numbers can go down to 50% to 80% from anywhere.”

That United Kingdom Agricultural and Horticultural Development Committee also recommends leaving the potato skins on before cooking potatoes. “This ensures that the nutrients and flavors aren’t lost during cooking, and you get all those nice vitamins too,” it says.

But again, potatoes are still very nutritious, even if you cook them without their skins.

“The question is, are you losing everything to the point where it will damage your health?” said Lungu. “I do not think so.”

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