What is the nutritional value of iceberg lettuce? This is a question that I get, ironically, from people who are not big vegetable eaters. We've all heard that iceberg lettuce has no nutrition and that iceberg lettuce is all water. The quick response to these statements is: Myth! And here is why.
Iceberg lettuce is a vegetable. All vegetables contain vitamins and minerals that we need to maintain our health. Different vegetables will contain more of some vitamins and minerals than others. No one vegetable can give you all the vitamins and minerals that you need.
The reasonable vegetable to compare iceberg lettuce to is another lettuce, such as romaine lettuce. Romaine lettuce has more vitamin A, vitamin K, and folate than iceberg lettuce. Iceberg lettuce is relatively low in these vitamins. Still, iceberg lettuce's lower vitamin A, vitamin K, and folate content does not make it bad for you! And it definitely does not contain zero nutritional value!
If the only vegetable or fruit you ever ate was iceberg lettuce, you might run into some nutritional deficiencies. But if you also eat a variety of other fruits and vegetables, even if you eat no other types of lettuce besides iceberg lettuce, it is exceedingly unlikely that you will have any nutritional deficiencies from your low-lettuce diet.
I think that a good question to ask is if you should be eating more vegetables, not if you should avoid a particular vegetable because it happens to have a lower vitamin and mineral content than another vegetable. The exact nutritional value of iceberg lettuce, or any vegetable actually, is irrelevant to most peoples' diet.