Lettuce, in general, contributes very few calories to the diet because, as pointed out by the Spanish Federation of Nutrition (FEN), it stands out for having a high water content (95%). That's why these types of vegetables are often used in weight-loss diets. However, lettuce is a source of vitamin C (4 mg) and folates (136 μg). "One serving of lettuce accounts for 15% of the recommended intake of vitamin C and folates," stated the agency. In addition, it has small amounts of phosphorus, potassium, iron, and calcium. "However, one has to remember that the intense green leaves, which are usually the least tender, are the richest in vitamins and minerals," they added.
In other words, the lettuce varieties that have a more intense green color are the richest in nutrients. This is the case of Romaine lettuce, which has a more intense green than the Iceberg variety. Thus, while the Romaine variety provides 2.1 g of fiber, the Iceberg variety barely has 1.2 g of fiber. The same applies to vitamin C. Romaine lettuce contains 4 mg and the Iceberg only contains 2.8 mg. The exact same thing happens with their vitamin A, folic acid, and magnesium levels. In addition, the Iceberg variety has less flavor than the Romaine variety.
Iceberg lettuce, one of the favorite lettuce varieties in countries such as the United States or the United Kingdom, has fewer nutrients than almost any green leafy vegetables that we can include in a salad.
Thus, we can say that there are green vegetable options that are much more nutritious than Iceberg lettuce when choosing between varieties to make a salad. Some time ago, the Harvard University School of Public Health published an article about which vegetables are the best from the nutritional point of view when it comes to making a green salad. The study states that, although Iceberg lettuce contains folic acid and vitamin A, it is the least nutrient-dense lettuce variety. "I am not recommending that you avoid Iceberg lettuce. I'm only stating that it's better to make salads with other types of vegetables," stated Elisabeth Moore, a dietitian-nutritionist at a medical center affiliated with the prestigious university.
