Single nutrient malnutrition...

Suppose you had otherwise healthy humans in a situation where they
were missing just one key nutrient in an otherwise adequate diet. For
ex, for some reason they're getting no, say, vitamin B or no zinc
(never mind why). What would specific sort of symptoms be, what would
be the first sign and how long would the various effects take for most
of the major nutrients?

(Some of the effects are well known, of course, like scurvy with
vitamin C or anemia with iron, but what about the other nutrients, and
what sort of early warning signs might exist?

(Keeping in mind that their diets are otherwise adequate or more than
adequate and the people are healthy to begin with.)