Once a week is what I do! Remember that if you have what I call a "high sodium" day, that you can "gain" 3 or 4 lbs overnight! It's NOT a "real" gain tho...to gain 3 lbs in a day you'd have to consume 10500 calories ABOVE maintenance! It's water weight caused by the sodium, so when you step on the scales, and it reads a higher number than the last time you weighed in, consider what you've had to eat in the past 2 or 3 days. If you know you stuck to your calorie limits, and remember eating higher sodium levels, consider that it's not fat! Drink lots of water and it should be gone in 2 or 3 days. You need to flush the salt out of your system.
I'm not losing this week, need to concentrate more! I'm holding steady tho, so in my mind, that's a win!