as far as I know:
In the UK "an item of fruit" can be replaced with "a fruit".
In the USA "an item of fruit" can be replaced with "a piece of fruit".
For example:
(1a)John ate three fruits: two apples and a pear. - correct for most Britons
(1b)John ate three pieces of fruit: two apples and a pear. - correct for most Americans
I'm interested whether we can use the word "food" the same way as "fruit" or not.
I mean: is it correct that:
In the UK "an article/item of food" can be replaced with "a food".
In the USA "an article/item of food" can be replaced with "a piece of food".
If you need an example, here is what I could come up with:
(2a)Bob bought three foods: bananas for himself, bananas for his father and nuts for his mother. - is it correct in the UK?
(2b)Bob bought three pieces of food: bananas for himself, bananas for his father and nuts for his mother. - is it correct in the USA?
If (2a) & (2b) sound odd I will be glad if you offer your variants.
Upd. 1: I was told in the comments below (2b) is incorrect because:
"Each banana and each nut would be considered a separate piece"
but then maybe (2c) is correct:
(2c)Bob bought FIVE pieces of food: two bananas for himself, two bananas for his father and a pack of nuts for his mother. - is it correct in the USA?
Upd. 2: I was told in the comments below (2c) is also incorrect because:
"A pack of nuts is not a piece of food" but "an item of food."
then (2d) must be correct:
(2d)Bob bought SEVEN pieces of food: two bananas for himself, two bananas for his father and three tomatoes for his mother. - is it correct in the USA?