IMO, the main issue with weighing once a week is what happens if weight fluctuations are not on your side on that one day? Weighing every day can be kind of stressful, but it helps you understand trends (weight going up if you ate more carbs, more sodium, or more volume). There are also apps (like Happy Scale on iOS or Libra on Android) that will smooth out your data for you. I use a Google spreadsheet to accomplish that same thing since it's cross-platform.In the past week my weight has been fluctuating from 222 lbs down to 217 lbs up to 222lbs again. Its pretty disheartening. Im going to try to only weigh myself once a week. Maybe once a Saturday in the morning after waking up.