There are many causes behind low immunity, but one of the best ways to counter this deficiency is by improving your diet. Leafy green vegetables are not only chock full of essential vitamins and minerals that our body requires, including vitamins A, E, B, iron and calcium, but also boasts antioxidants that work in concert with the immune system to eliminate foreign pathogens and prevent chronic disease. If you want to amp up your immune system, a plate of spinach or kale is a wonderful place to start!