Skin On Or Skin Off?

Whenever I pack lunches for my kids, I try to include plenty of fresh fruits and vegetables. Sometimes food texture can be a bit of an issue for kids, so I’ve been known to peel a cucumber or carrot before adding it in. When I’m cooking dinner, I also might peel potatoes if I’m preparing them roasted, mashed, or adding to a stew or soup.

In this post, I want to explore the nutrients you might be throwing into your compost bin by peeling cucumbers, carrots, and potatoes. While we don’t peel apples in our house (except for when we make an apple pie), I wonder what nutrients we can obtain from apple skin. I’ve also heard that pesticides tend to concentrate in the skin of a fruit or vegetable. Even though my family eats organic, in this post, I also want to find out if there’s truth to this long-standing belief of mine.

What’s in the skin?

Let’s start with cucumbers. I actually like cucumber skin, it just gives more firmness to the fruit. (Yes, technically, a cucumber is a fruit. Read this interesting article to find out what makes a fruit a fruit and a vegetable a vegetable). According to this Penn State University health post, the vitamin content of cucumber skin wasn’t much to write home about. However, it does offer a great source of fiber for the digestive tract and delivers minerals such as potassium. It also adds magnesium along with silica, a lesser known mineral that promotes good nail health.

Next up, carrots. I confess that the grit between my teeth that I occasionally experience if I don’t peel a carrot sets me a bit on edge. (The same goes for potatoes, but we’ll get to them next.) As I searched for information on the nutritional value of carrot skin, I encountered this answer by a health writer for The New York Times. The subject matter expert referenced in the answer explained that in most cases, if the color of the skin matches the interior of the vegetable, then you’re really not losing nutrients by peeling. That same expert goes on to say that even with radishes, which have vastly different exterior and interior colors. Apparently, the color comes from a natural food coloring that doesn’t really add more nutrients. But who peels radishes? I like them for the color that they add! What did catch my eye was the statement by an expert. It was said by an associate professor of horticulture at Cornell University who specialized in root vegetables. He said, “The big exception is the potato. There’s a lot of nutrition in the skin.”

I was on the edge of my seat.

From Livestrong, I discovered that potato skin may account for up to half the nutrients found in a potato. Partly, that’s because when a potato is cooked in it’s skin, you keep the nutrients in the potato flesh from leeching out. Combined, the skin and flesh of a potato provide around 15 percent and 45 percent, respectively, of the recommended daily allowance of potassium and Vitamin C. But, as the saying goes, “How ‘bout dem apples?” Huffington Post explains why you should never peel the skin off an apple. Why? You lose more than half the fiber, a quarter of the Vitamin C, and a three-fifths of the Vitamin A. Plus, the apple skin contains quercetin, a compound found to improve lung health, protect your memory, and potentially inhibit the growth of cancer cells.

Do pesticides concentrate in the peel?

So on to researching my conventional belief that pesticides concentrate in the peel of product. Actually–it’s not really clear that they do. What I did discover, through this NBC News article, which used the Environmental Working Group (EWG) as it’s information source, is that the thickness of the skin tends to impact how much pesticide gets absorbed into the fruit or vegetable. So there is a relationship. The article outlines which fruits and vegetables are more prone to absorbing pesticides, and how to avoid ingesting the pesticides when you can’t buy organic. It turns out that apples and potatoes are definitely best bought organic to avoid those pesticides. For the direct source of this information, head over to EWG.org. But as you’ll see, it’s not really as straightforward as all that.

Cleaning fruits and vegetables when you don’t peel

I always keep a dedicated scrub brush by my sink that I use to get as much dirt and debris off my produce as I can. To remove most pesticide residue from the skin (not the inside, mind you) of a fruit or vegetable, after you wash or scrub it, use this spray recommended on Good Green Habits. The comments in the Good Green Habits article raised a question about organic really being pesticide-free. This article in Scientific American stated that even organic produce often has pesticides sprayed on it.

Confused? I was, too.

It turns out that labeling a food “organic” in the U.S. only means that if pesticides or chemicals are used, they have to be derived from natural sources. For me, it’s back to the drawing board on how to best choose my produce.

Back to the question: Skin on or skin off?

So it turns out that of the four produce items I discussed, the only one that I’m not losing fiber or nutritional value from peeling is carrots. I tend to buy organic most of the time, but knowing what I now know about organic produce, I think I’ll keep a spray bottle of the cleaning solution. I can at least get the residue off when I don’t peel my fruits and vegetables. Also, I’ll be doing more research on how to truly buy pesticide free produce.

This week I posted a delicious recipe for One-Pot Tender Beef and Vegetable Soup. The recipe calls for carrots and potatoes. Although I do suggest peeling the potato, if you are okay with the texture of the skin in the soup. You might just save yourself time and trouble. But, you’ll gain some nutrients by just leaving the skin on! What do you know about the health benefits of the skin of produce? Do you have tricks for purchasing organic, pesticide-free produce? Share your thoughts in the comments section. I’d love to hear them!