Oh, I didn't stop because of age (a lady never tells ;-)) - I stopped because they told me my iron was "borderline" the last time (never happened before) and I knew if I did it again I'd probably get sick. I haven't checked to see if it's back up yet.

If you're still well, I don't see why you'd need to stop, I saw lots of much older people still donating safely; I know you're so needed!