Romaine lettuce is a head lettuce variety that grows in tall, sturdy, green heads with crisp ribs down the middle of each leaf. The ribs, when broken, may exude a bitter white liquid.
Romaine lettuce is a source of vitamins A, C, K, and folate, and small amounts of calcium, iron, and potassium. Like all lettuces it is low in calories. Romaine lettuce is relatively low in antioxidants, but the darker green outer leaves are a more concentrated source of the antioxidants present in leafy greens.
Salad mixes, salads, sold as is, prepared meals, prepared sandwiches