mild weight gain

I'm 6 months from my RnY gastric bypass surgery.  I weigh myself twice a week (Mondays & Thursdays).  Today, for the first time in 6 months, instead of losing weight, I have gained two pounds.  I went from 291 this past Thursday, to 293 Today.  It's quite depressing.  I've been told before, going on long term and serious diets, there will occasionally be weeks where no weight is lost, and even the occasion pound in gained.

I wish I had an explanation.  My diet has not changed.  I did, this past week begin to incorporate abdominal crunches in my work-out routine.  I also started to sip some diet soda.  And I mean sip, maybe a total of a half a can of diet soda for the whole week.  (I know carbonation is tricky for some people, but I've been fortunate, or unfortunate and have not had any dumping or any "typical" pouch problems.)  To me, it feels much like a normal stomach, it's just able to hold half, or a fraction of what a "normal" stomach might be able to hold.

Is this small weight gain something to freak out about?  I'm trying to not to.  I just want to muscle through it and hope for more loss next time on the scale.  Have other folks seen, a tiny gain occasionally, for whatever unexplainable reason?  I'm very nervous.  I just hope this is a little bit normal and not nearly the end of my losing.

[bowel movements and all aside, I had one the last night (so it's not that...)]

I'd love some thoughts...

some state: 25 years-old, 6'2, male - RNY on 02/12/2009, started at 449, current 293, total loss 156 pounds, with another 93 pounds to lose.

Sometimes your body will just hold on to fluid.  I had a friend point out how much a gallon of water weighs and he said that could easily be gone in a day.  Also, you will hit stalls along the journey.  Your body has to adjust to your weight loss. 

Ah, to be fairly young and be able to get WLS.  I sometimes wi**** had been more available 20 years ago.  You should be able to lead a happy productive life.  It makes me a bit envious.

You have a great gift.  Make the most of it. Potein shakes and bars are a must.  I'am gaining lean mass and loving it.  Up 2-4 lbs and losing fat mass.
Hell I cant remember when I was 25.  Lets see, Oh yea, a factory rep in VA. new wife and lots of dreams

First of all, rest assured that you are normal.  Stalls and small gains are normal. 

A concern about carbonation:  as a former Diet Coke junkie, my nut was very adamant about staying away from carbonation.  It's not because of dumping, but because the effervescent gases expand the pouch, allowing you to eat more, and thus slowing down the rate of weight loss.  I am not a nutritionist and I don't play one on TV, but maybe the pouch expansion from carbonation caused you to eat more food.  It's one possibility to consider!

I don't miss the Diet Coke at all right now, and it's been about four months since the last one prior to my two-week pre-op diet.  I don't intend to have another one - a small price to pay for the long-term benefits of WLS.

Stick to the program and the numbers will keep going downward.  You've done it for 156 pounds so far - do it for the next ten pounds ... and then the next ten ... and the next ... !