Hmm, could be.  I usually do my business when I wake up in the morning, then again when I get home at night from work.  I figure that is my daily cycle, unless I drink three tall cups of coffee, then I usually have to hit the head right after lunch as well, though that does push the evening cycle out a little later.  
I've pretty much always been like this.  I'm 44 now, and the only real change was when I was in Baghdad I noticed that even though my schedule was the same, the volume was less.  Even then I was drinking upwards of 2 gallons a day.
I guess I just have a monster bladder.  Go figure <img src="/images/graemlins/blush.gif" alt="" /> <img src="/images/graemlins/smirk.gif" alt="" /> 
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)