While mango skin isn’t considered dangerous to eat, it does contain a very specific toxin that is rarely found in nature, called urushiol. This is the same chemical compound found in poison ivy that can cause inflammation and redness on the skin.
While the amounts of urushiol in the skin of mangoes is quite small, if you are overly sensitive to this compound, it can cause inflammation and gastrointestinal discomfort.
Aside from that, however, the other active ingredients and antioxidants found in the skin, such as valuable polyphenolic compounds and carotenoids (partly responsible for the colour of mangoes). These compounds help to reduce oxidative stress and prevent chronic disease, including cancer and heart disease.
In addition to the beneficial antioxidants in the skin, studies have also found high levels of vitamin C, vitamin E and dietary fibre. These nutrients are densely concentrated in the skin, and can aid in the maintenance of your immune system, skin health, and gastrointestinal functions.
However, not only is there the chance of a negative allergic reaction to the compounds in the skin, but the skin also has a slightly waxy and rubbery feel, as well as a bitter taste, which may be stronger or weaker depending on how ripe the fruit is. The fibrous nature of the skin also means that you’ll be chewing it for a while, as opposed to the tender, sweet and delicious flesh of the fruit.
Additionally, you may not want to eat mango skin unless they are organic, as this is one of the fruits that is commonly sprayed with pesticides, which may be unpleasant to consume, and potentially unhealthy. Before eating any fruit with its peel or skin, it is wise to thoroughly wash them.