Q. Is it true that most of a carrot's nutrients are in or just below the skin, so it shouldn't be peeled?
A. Emily S. Mohn, PhD, and Elizabeth J. Johnson, PhD, both scientists in Tufts' HNRCA Antioxidants Research Laboratory, respond: "Carrots consist of three major layers: 1) the peel/skin (outermost layer), 2) the phloem (intermediate layer) and 3) the xylem (inner core). Generally, all of the peel and a very small portion of the phloem are removed when a carrot is peeled.
"Vitamin C and niacin are most concentrated in the peel but can be found in appreciable amounts in the phloem. As for beta-carotene (an orange pigment and plant form of vitamin A), the peel and phloem have approximately equal amounts. That is why both peeled and unpeeled carrots have the same orange color. The xylem contains the lowest amount (about 10% of the total) of beta-carotene. But, the xylem contains the majority of the calcium, potassium, magnesium and phosphorus present in carrots. And, both peeled and unpeeled carrots are good sources of fiber.
"As for carrots' phytonutrients (compounds with potential, but uncertain health benefits), a little more than half are found in the peel. However, about 40% of the phytonutrients are found in the phloem and about 10% in the xylem.
"Overall, while removing the peel reduces some phytonutrients and small amounts of the vitamins and minerals in carrots, there is plenty of nutritional value left behind. Remember, the peel is only a small portion of the total vegetable. If you prefer the taste, texture or look of peeled carrots (or the convenience of baby carrots), you can certainly incorporate them into a healthy dietary pattern. But, this root vegetable is perfectly safe to eat unpeeled, as long as it is adequately washed."