I tell people (and nutrition clients) all the time:
Do not tie your happiness to your weight on the scale in the morning.
Easier said than done, especially for someone that is intently focused on losing weight.
But here’s the thing:
Weight is fluid.
Even for someone who is at their optimal body weight, and has a very consistent handle on which foods, quantities, & frequencies work well for their body (and which do not), their weight is not exactly the same every morning.
Neither are their caloric needs, body fat, body water, and much more.
There’s always some fluctuation up or down.
More than that, what you weight today does not only depend on what you ate yesterday.
It also depends on what you ate recently, especially in the last three or four days.
It may take your body 3, 4, perhaps even 7 days or more to fully optimal balance after eating (or drinking) certain foods.
Checking in on your scale daily is healthy for most people, as long as it’s paired with the knowledge that day-to-day readings of your weight in pounds are only 1 piece of the puzzle.
Matt Fried 