The nutritionist I had an appointment with a couple of weeks ago told me the same thing... 1 cup ='s a serving of cantaloupe, honeydew, or watermelon.
Tracy A.
From the info I was given one serving of veggies is 1/2 cup cooked or 1 cup raw, and the list includes lettuce.
However, the nutritionist I saw told me I could to 2 cups of lettuce as one serving, but only on lettuce.
Hope that helps.
Tracy A.