Due to its rich nutrient content, this buttery lettuce provides you with lots of carotenoid antioxidants such as beta carotene, zeaxanthin, and lutein. For this reason, it protects your eyes from macular degeneration. Moreover, butterhead lettuce contains a very high amount of iron. It's important to realize that this nutrient is crucial for creating red blood cells in your body. It's particularly high in folate and Vitamin A and K. In addition, butter lettuce is a low-fat, low-calorie, low-sodium salad choice that literally goes with any main course.