Are you talking about blokes you're interested in dating or who might be interested in dating you? If so, maybe you need to change the age range of the men you're looking at. If they seem to think you're "too old" (I say that because you asked about "knocking a few years off?"), then go places where there is a slightly older crowd than you usually seek out.
If you're just talking about making new friends, I don't see why age would be an issue. But if it is, again, I give the same advice.
Frankly, I don't see any reason to mention your age, unless you're asked. But I take it they're asking.