I did a lot of walking on my recent vacation but gained weight

[gvanzant1]

I recently went to Disney World with the family.  Over 4 days, I walked over 75,000 steps (almost 19,000 steps/day).  My eating was no different than usual: a couple of granola bars for breakfast, sandwich for lunch, and a smaller than usual dinner; no snacking and no desserts (we were too busy to stop to eat).  Yet I GAINED weight.  I come back to my sedentary office work where I barely break 6,500 steps/day, snack more in the afternoon, top off dinner with dessert, and I LOSE weight.  What gives? 

[WendyB]

Sounds like you were not eating enough. You do need to eat to lose weight. Plus the added activity.

[Baltoscott]

Changes weight scale readings are dramatically influenced by how hydrated you when weighing.  This changes from hour to hour and day to day and you probably drank more than usual while doing all that extra walking.  

A better measure of weight change before and after a vacation is to weigh in daily the week before and the week after and then compare the weekly averages instead of the scale reading the day before and after (weekly averages even out the daily fluctuations in water retention).