Dealing with food allergies and sensitivities

It must be hard for restaurants to deal with various food allergies, sensitivities, and preferences. Some add ‘GF’ for gluten-free or ‘V’ for vegetarian to their menu listings to indicate the items that suit those categories, but what about the rest?

One Chinese restaurant I ate at in Utah tackled it this way — they had an entire submenu for many of the main food allergies/sensitivities/preferences. I thought it was a good way to tackle the issue — it had to be easier than someone with one of those intolerances trying to scan every menu item looking for a particular code letter.