What Does "easy on the" Mean in Food Preparation?

If I walk into a restaurant and order a sandwich that comes with lettuce, and say "easy on the lettuce", would that mean that I wanted no lettuce at all, or simply less than normally comes with the sandwich?

I'm primarily referring to American usage, but would be curious about other locales as well.

It would mean you wanted less than normally comes with the sandwich.

'go easy' definition from Cambridge Dictionaries Online

I can't offer detailed evidence to support this, but I think it's quite a universal phrase. The link suggests it is common in British English and I know from experience it's also common here in Ireland.

Go easy on the X means Do not add too much X.

Someone who likes mayonnaise but does not want a lot of it might say Go easy on the mayo.

Someone who likes a little bit of pepper, but not too much, might say Go easy on the pepper.