Why two weeks?

I read somewhere that Invisalign recommends wearing each set of aligners for 250 to 300 hours - hence, the 2 week schedule (called "activation time").  The closer to 300 hours, the better.  I think at some point many folks were swapping aligners after only 1 week, and results were not as good.

I'm just an armchair orthodontist, but I suspect that teeth move in the first week and stabilize the second, so they are more ready to move when the aligners are swapped.  That would explain the pressure in week one, and relative looseness in week two, especially near the end as I am now.  It is tempting to swap early, but I will wait out the full two weeks and swap on Monday night.  Conventional braces are generally tightened only once a month, so Invisalign may move the teeth more efficiently.

On the additional benefits front, the Invisalign diet continues.  I am using the aligners as a very good excuse not to snack.  I have combined this with a low carb approach, and am down 15 lbs. in 4 weeks.