REVEALED: Why you should eat the skin of fruit and vegetables - even oranges and pineapples

According to experts, it would seem that eating the skin of fruit and veg could help improve your mood, make you look forever young ­(maybe) and even kick cancer.

Various studies seem to have confirmed this, with fruits such as banana, kiwi and even pineapple in the list of fruits which should keep their skins ON to reap all the benefits.

So is it time to ditch your peeler?

Oranges

Save your fingernails and eat the whole fruit, peel and all.

According to a 2004 study in the Journal of Agriculture and Food ­Chemistry, powerful ­antioxidants called super flavonoids found in orange and tangerine peels can reduce levels of total cholesterol and “bad” LDL ­cholesterol, without lowering the “good” HDL levels.

Antioxidants mop up damaging free radicals which are produced by our bodies when we breathe and eat and are linked to disease.

Ones obtained from the peel were 20 times more powerful than those from the juice.

“The same goes for all citrus fruits,” says nutritionist Anita Bean.

“Although we throw away the peel because of the bitter taste, the pith contains high levels of pectin, a component of dietary fibre known for its jam-setting qualities, which helps lower cholesterol and acts like a prebiotic, helping colonise the gut with beneficial bacteria.”

Apples

Peeling the skin off an apple means throwing away the fibre. “Almost half the vitamin C lies within 1mm of the skin’s surface so you’re losing that too,” Anita says.

“And most of the fragrance cells are in the skin, so you can have a tasteless fruit if you peel it.”

Red apple skins are particularly rich in anthocyanins, which are antioxidants that may protect against several types of cancer, in particular ­prostate cancer.

Yellow apple skins contain carotenoids like betacarotene which help maintain healthy eyes, combat cancers and protect against heart disease.

And green apple skins are rich in lutein, which can help reduce the risk of cataracts and birth defects and also protect against cancers.

“The bright colour of apple skins is completely indicative of the healthy polyphenol content in it,” Anita adds.

The core and pips don’t contain higher levels of antioxidants but are an excellent source of soluble fibre to help stabilise blood sugar and aid digestion.

Garlic

According to a 2003 report in the Journal of Agricultural and Food ­Chemistry, garlic skin is recognised for having powerful antioxidant properties, and researchers from the Wakunaga Pharmaceutical company in Japan ­identified six antioxidant compounds within its skin.

“Peeling garlic removes phenylpropanoid ­antioxidants found in the velvety membrane which help fight the ageing process and protect the heart,” explains Anita.

Bananas

The uses for banana skins extend beyond slapstick pranks. A Taiwanese research team from Chung Shan Medical University discovered that banana peel extract can ease depression because it’s rich in the mood-balancing hormone serotonin.

It also protects your retinas because it contains lutein, an antioxidant from the carotenoid family, which protects eye cells from exposure to ultraviolet light, a cause of cataracts.

In clinical tests, the research team exposed two groups of retina cells – one a control group and the other group soaked in a solution of banana peel extract – to strong light six hours a day for two days.

At the end of the ­experiment the control group had died while the group soaked in banana peel extract suffered no damage. There was no difference between using skins that had gone brown and those that were still yellow.

Potatoes

You’ll double your intake of nutrients by eating the skin, says Anita. “Just one fist-sized potato skin provides half your RDA of soluble fibre, potassium, phosphorous, iron, zinc and vitamin C,” she says.

“Pound for pound, potatoes contain more vitamin C than oranges, so are perfect for anyone looking to ward off colds and boost their immune system.”

Pineapple

Along with fibre and vitamin C, pineapple’s real health benefits lie in the enzyme bromelain, which can break down many times its own weight of protein in a few minutes.

This makes it excellent for people with indigestion as food is digested and absorbed quicker, reducing bloating, Anita says.

Bromelain is an anti-inflammatory too, so eat pineapple if you are suffering from hay fever, arthritis or gout.

“The middle core actually contains twice the bromelain concentration of the fruit – and canning destroys the bromelain content, so throwing away the core is a real no-no ­nutritionally,” she says.