It's not impolite to ask - I don't mind answering questions about it. "Congenital Anosmia" is the correct term. It's fairly serious when someone loses their sense of smell, and can cause weight loss and depression. It can also be a symptom of some fairly serious conditions (e.g. Parkinson's).

For food - I prefer strong flavors (smoked salmon, capers, onions). Subtle flavors like spices are lost on me - basil, spinach, and mint all taste the same. Cheeses can be strong - I think I could tell the difference between blue cheese and provolone, but I haven't done an experiment. I'll have to try that sometime.

It is possible I have a very week sense of smell. I can kind of smell coffee, and there are a few times I've smelled an orange, but that hasn't been reproducible. My dog got sprayed by a skunk one time, and I couldn't smell that, so I think it's accurate to say I don't have a sense of smell.

I can "smell" things like vinegar and bleach, but I think that's the trigeminal nerve. I can't tell the difference between white vinegar and balsamic vinegar, however.

My mom can't smell either - nor could her dad.