Ask the average person and they'll probably tell you that people in medieval Europe didn't eat any vegetables (except possibly for the Irish, who were evidently eating potatoes for centuries before they were brought from the Americas, but that's a whole different issue).
vegetables grown for no reason
Some background: I just spent the weekend traveling, and this morning it occurred to me that every time I eat in restaurants for more than a couple of days I start to feel incredibly vegetable-deprived.
Mind you, I'm not a vegetarian. I'm not even one of those people who are forever grazing on carrots and celery and whatnot. In fact I'm pretty sure I don't eat anywhere near the number of servings of vegetables currently recommended by any of the health authorities. That's why this disturbs me so much. If I'm feeling veggie deprived when eating restaurant food, then there really must be a serious lack of green things there.
Let's think about the typical restaurant meal for a minute. If it's fast-food then there's almost no chance for plants. Maybe there's a shred of lettuce or tomato or pickle - about 1/1000000th of a full serving. French fries come from a plant, but they're really just starch and fat - not much veggie goodness there. And no, before anyone says it, ketchup is not a vegetable.
Other restaurants may do slightly better. A small salad, coleslaw, maybe even green beans or broccoli (when I was in England I found they served peas as frequently as the US does broccoli - a pointless observation, but there it is), but even that seems to be more the exception than the rule.
Now compare that to the menus from meals served to medieval royalty. It can be hard to tell what's going on in a lot of these - there are lots of meat references and few vegetable ones, but that's not too different from modern menus. Looking at household accounts and dietetic manuals from the time though, it's pretty clear that medieval people were eating plenty of vegetables. Apparently only a relative few of the recipes for vegetables were thought important enough to write down.
They ate salads and cooked turnips (sliced and layered with cheese and butter) and sometimes cooked cauliflower and such. Occasionally spinach or beets, parsnips and carrots. Now that I think about it, it really doesn't sound that different from the modern diet. The average person likes to eat meat, starchy-foods, and sweets. They'll eat some vegetables, and maybe like them too, but for most people it's not the first thing they'll reach for at the table.
Interesting. So apparently I'm an exception and not the norm. There's a surprise.