Yes they are ...
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Collard Greens (one 190g serving) contains more nutrients per gram than most foods out there.
They are a great source of Vitamin C, Vitamin K, and Folate. These flavonoids have strong antioxidant properties with many health benefits.
One 1 cup of fresh, chopped collard greens contain 58% 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.
Collard Greens are also an excellent source of vitamin-K; 190 g of collard greens provide 1045% of the RDA. Vitamin-K, a great antioxidant, is required for blood clotting and building healthy bones.
Antioxidants such as the ones found in collard greens 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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