The healthiest type of lettuce that is number 1 on the list is Kale and then after Kale the other types of healthiest lettuce is Spinach, Swiss Chard, Watercress, Romaine, Butter Lettuce and Red or Green leaf lettuce.
All types of lettuce are healthy to eat so eating a variety of lettuce is good for your overall health and even though Iceberg lettuce gets a bad rap sometimes for being not the healthiest lettuce it's still a great lettuce and is nice and refreshing in salads especially during the summer months due to it's high water content.