I see all over the place 5 a day, as in eat 5 servings a day of Fruits and Vegetables. To me broccoli, carrots, kale, etc seem like good vegetables. How about Iceberg Lettuce - I have been told it is not very nutritous. And what about potatoes - they seem full of starch and carbs to me.
I wouldn’t call potatoes veggies. Lettuce is good for filler but not much else.
The US Government has a website called 5aday (dot) gove
That’ll help you out
Potato was chosen “vegetable of the month,” for some month, by the good people up in the US gov:
http://www.fruitsandveggiesmatter.gov/month/potato.html
Iceberg lettuce was also selected, among other lettuces, by the same people, for the same distinction, although it was called “the least nutritious of the lettuces,” or some such:
http://www.fruitsandveggiesmatter.gov/month/lettuce.html
Potatoes are high in fiber and vitamin C, potassium, and a bunch more – as well as carbs, but I don’t see how the latter fact is relevant for this discussion.
“Least” or “most” nutritious lettuce is kind of pointless if you are on a diet as no lettuce is going to be nutrition heavy. I’m not a big iceberg lettuce fan because it’s kind of tasteless and stiff vs other lettuces, but apparently it’s a big favorite in Japan. Lettuce’s main place is modern diet is as filler and as a (minor) bit of roughage.
A lot of whether a vegetable is “good” or “bad” is how it is prepared. Potatoes, for example, are very good for you by themselves but loaded up with sour cream and bacon bits and butter and cheese… eh, you probably don’t need all those fats and calories. Iceberg lettuce, as mentioned, is the least nutritious of lettuces, but it does fill you up a bit and has few calories… until you load it up with fatty dressing.
If you eat four other fruits/vegetables a day and make iceberg lettuce #5 no harm done. Eating five servings of iceberg lettuce and no other vegetables… not so good.
Iceberg lettuce has thiamin, B6, folate, vitamin A, vitamin C, vitamin K, iron, potassium, manganese and fibre. Other types of lettuce have even more vitamins and minerals, but iceberg compares OK to other veggies like cucumber, or bell peppers. It fulfils the basic veggie function of filling you up without lots of calories, and providing useful nutrients as well.
Potatoes provide a smaller range of nutrients than lettuce, but a good amount of vitamin C in particular, plus manganese, potassium, vitamin B6 and some fibre. They have a lot more calories than your standard vegetable. I count them in the bread/cereals section of the food pyramid, though they have more vitamins etc. than most things you’d find there.
None of the 5-a-day schemes I’ve heard of permit potatoes as one of the 5 - for example:
http://info.cancerresearchuk.org/healthyliving/dietandhealthyeating/fiveaday/