Next is the perennial, burger-topping iceberg lettuce. You'll need 33 cups of ... Vitamin A is an essential part of normal vision and a health immune system. This pretty red and green leaf is ...

Here's which types of lettuce are most popular, why these greens are good for you and what you need to be mindful of as you include more in your diet.

Messer praises the vitamin A and C content of many types of lettuce for improving eye health, immune function and skin health. "Vitamin A also supports cell growth and repair," she adds.