"But, what about those day-to-day fluctuations in body weight the diet industry mentions? Won't those fluctuations skew your weigh-in measurements? Brown answers, "You simply learn to take the fluctuations into account. It doesn't mean you ignore weighing in. These fluctuations are usually caused by water retention and changes in gastrointestinal contents. My book, The Body Fat Guide, shows you how to separate these types of fluctuations from changes in your muscle and body fat levels."
"Remember," summarizes Brown, "it only takes 1 day to gain body fat or lose muscle! Why wait a whole week to measure it? Weight management is a day-by-day process. The sooner you are able to see your weight going off track, the sooner you can take action to get back on track.""