Nutritional Benefits of Green Beans One cup of green beans packs a mighty nutritional punch. One cup of green beans has four grams of fiber, most of which is soluble fiber. This type of fiber can help to lower LDL cholesterol (“unhealthy” cholesterol) and blood pressure. Green beans are also a good source of vitamin A and C. Vitamin C is an antioxidant that helps the immune system function and protects skin. Vitamin A is important for skin health, vision, and our immune system. Green beans are also a good source of manganese, which helps support our metabolism, bone health, and wound healing