Citrus Against Cancer: It’s in the Peel!

Did you know…

…citrus peels may help protect against and prevent cancer?

Fresh tangerines on a wooden tableThe cancer-protective benefits of citrus fruits have long been talked about. Not only are citrus fruits associated with a 10% reduction in breast cancer risk, but orange juice consumption in particular has exhibited a defensive influence on childhood leukemia, and the antioxidant impact of vitamin C is undeniable.

Now, however, research has shown revealed other anti-cancer agents found not only in the fruit of citrus, but in the peels, along with a compound that enhances the effectiveness of a DNA-repairing enzyme. Citrus peels are, after all, a fruit’s first line of defense, and as such are loaded with antimicrobial, antioxidant, and even anti-cancer attributes.

The Surprising Power of Peels

The peels of citrus fruits contain a carotenoid called beta cryptoxanthin, which may help repair broken strands of DNA. When toxins and carcinogens (cancer-causing substances) come in contact with cells, DNA strands can become severed. DNA repair enzymes then reconnect these broken strands as best they are able. Laboratory studies on in-vitro cells show that when you add in this citrus carotenoid, repair happens twice as fast!

Human trials confirm this speedy repair process. Two hours after drinking orange juice, test subjects had their blood drawn. It appears orange juice consumption diminished the DNA-damaging effects of a mutagenic chemical.

Citrus peels, such as a lemon peel, also contain modified citrus pectin (MCP) and limonoids. MCP has been shown to suppress the metastasis of prostate, breast, and skin cancers. And limonoids do much more than just make citrus peels slightly bitter; in-vitro and animals studies suggest limonoids can help inhibit the growth of cancer cells and spark cancer cell death.

Protection From Elevated Cholesterol, Diabetes, and Cancer

Citrus peel flavonoids— such as naringenin naringin tangeretin hesperidin … and hespereti—may all exert an anti-cancer influence. But the antioxidant flavone nobiletin is a standout. Found in the peels of oranges, tangerines, and mandarins, nobiletin has been shown to help lower harmful LDL cholesterol, protect against diabetes, and suppress cancer growth.

Several Japanese studies validate the anti-cancer potential of nobiletin. Researchers from NARO Western Region Agricultural Research Center in Japan found that nobiletin suppressed the spread of leukemia by enhancing the activity of natural killer cells. And a study from Taiwan’s Chung Shan Medical University revealed that nobiletin inhibited the production of leukemia cells.

Other studies show that nobiletin extracted from citrus peels may block the development of certain types of prostate, breast, liver, and stomach cancers.

Enjoying Citrus Peels

You can add a tangy zing to foods with the zest of citrus peels. Use a vegetable peeler or a paring knife to zest citrus fruits. Remove the thin, colored skin and leave behind the bitter pith. Add citrus zest to soups, salads, chickens, or fish.

If you want to use the whole peel, then do what the Moroccans do and preserve whole lemons in a brine made up of fresh lemon juice and salt. Ferment for 4 weeks, and then use the peel in salads, couscous, or tagines. When it comes to consuming citrus peels, health experts point out the obvious importance of choosing organic fruit and washing it before you eat those peels!