Yes they are ...
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Oranges (one 184g serving) contain more nutrients per gram than most foods out there.
They are a source of Vitamin C, Vitamin A, and B6. These flavonoids have strong antioxidant properties with many health benefits.
One serving of a fresh oranges contains 163% of daily recommended levels of vitamin-C. Vitamin-C is a moderately powerful antioxidant, which may help the human body develop resistance against infectious agents and attack the harmful oxygen free radicals.
Oranges are also an source of Vitamin B6; 184 g of oranges provide 6% of the RDA. Vitamin B6, a great antioxidant, is required for brain development and keeping a healthy nervous system.
Antioxidants such as the ones found in oranges are said to be essential for boosting immunity. Some of these may play an important role in helping improve your immune system to fight off flu and other viruses.
Eat and be healthy.
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