Lettuce is a low-calorie, leafy vegetable that is high in water content and a good source of various vitamins and minerals, with excellent source of vitamin K, providing over 100% of the recommended daily intake in a 100-gram serving. It's also a good source of vitamin A and vitamin C, providing approximately 15% and 10% of the recommended daily intake, respectively. Additionally, lettuce is a good source of folate and potassium, providing approximately 10% and 5% of the recommended daily intake, respectively.