String beans can be very nutritious. Although string beans are available all year long, it’s best to eat them when they are fresh throughout the summer and even into the early fall. String beans contain a variety of vitamins that are great for your health. There are a variety of benefits that you can enjoy by eating your string beans. For one, a serving of string beans contains enough vitamin K to help your bones to grow strong over time. String beans help prevent your bones from breaking down as well.