Yes they are ...
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Leeks (one 89g serving) are high in Vitamin C and Manganese. They also contain Vitamin A and Folate.
Vitamin A is a fat soluble vitamin that is essential for eye health. Not having enough may cause night blindness.
Vitamin C, also called ascorbic acid, is water soluble and is said to be good for your immune system. If you don't have enough you may develop scurvy and have other problems like wound healing.
Manganese helps the body form and repair connective tissues so it's really important for optimal health.
Folate, a form of Vitamin B9, is also water soluble and is needed to make DNA and RNA in the body. Luckily, vegetables like leeks are a good source.
Eat and be healthy.
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