food/s

You can use it when you are specifically making the point that there are different types of food.

e.g. There are 100 foods for sale in this supermarket.

Yes. It refers mostly to the separate ingredients, the raw materials as it were:

beans, root vegetables, meat, fish, cereals, bread. These are foods, aka foodstuffs.

Cooked together in recipes, they are food.

I think that's okay as a general rule.

I kind of hoped for more opinions on this.

But I think I'm right. It works in Britain, anyway.

Interesting.

I was running some common things I would say through my head, and realize I seldom use the word foods.

For instance, in Robert's sentence, I would say "There are 100 different TYPES of food in this store"

I don't think I say foodstuffs, but rather, types of foodstuff, or all this foodstuff.

I honestly can't say if this is a personal preference, or if it's a difference between the way we speak english.

I'd like to get some other people views too.

btw, I always find it odd when a Brit says "maths", I'm sure it sounds just as off to you when a Yank says "math"

I don't think it's a raw materials thing, so much as a different countable items in a variety thing.

e.g. The menu tonight included 4 spicy foods that I'd never heard of. (different dishes)

Here's a pattern in other words to show the differentiation factor I'm talking about:

The meeting of nations was a beautiful reunion of diverse peoples. (different races or cultures)

He was a world renowned biologist, with 4 fishes to his name. (different species of fish)

There are times when I don't have as much time as I want. (different instances)

That sentence would be unusual in Britain, I feel.

But I agree about the other plurals of course.

I think in written British English (as in American), in such a situation you would be more likely to call the items on a menu "dishes", and, except in notes, text messages etc, one writes numbers out as words:

four spicy foods.

Five hundred miles.

A million years.

We might say, "I like Mexican and Chinese food."

Not "foods", oh no.