What are health benefits of orange?

Nutrients in oranges are plentiful and diverse. The fruit is low in calories, contains no saturated fats or cholesterol, but rich in dietary fiber, pectin. Pectin, by its virtue as a bulk laxative, helps protect the mucosa of the colon by decreasing its exposure time to toxic substances as well as by binding to cancer-causing chemicals in the colon. By binding to bile acids in the colon, pectin has also been shown to reduce blood cholesterol levels by decreasing its re-absorption in the colon.  

Oranges, like other citrus fruits, are an excellent source of vitamin-C (provides 48.5 mg per 100 g, about 81% of DRI); Vitamin-C is a powerful natural antioxidant. Consumption of foods rich in vitamin-C helps the human body develop resistance against infectious agents and scavenge harmful, pro-inflammatory free radicals from the blood.

Orange fruit contains a variety of phytochemicals. Hesperetin, naringin, and naringenin are flavonoids found in citrus fruits. Naringenin is found to have a bioactive effect on human health as antioxidant, free radical scavenger, anti-inflammatory, and immune system modulator. This substance has also been shown to reduce oxidant injury to DNA in-vitro studies. Total antioxidant strength (ORAC) of oranges (navel variety) is 1,819 µmol TE/100 g.

Oranges also contain very good levels of vitamin-A, and other flavonoid antioxidants such as α and β -carotenes, β -cryptoxanthin, zeaxanthin and lutein. These compounds have been known to have antioxidant properties. Vitamin-A also required for maintaining healthy mucosa and skin and essential for good eyesight. Consumption of natural fruits rich in flavonoids helps human body protect from lung and oral cavity cancers.  

It is also a very good source of B-complex vitamins such as thiamin, pyridoxine, and folates. These vitamins are essential in the sense that the human body requires them from external sources to replenish.

Orange fruit also contains some amount of minerals like potassium and calcium. Potassium is an important component of cell and body fluids that helps control heart rate and blood pressure through countering pressing effects of sodium.

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