Can You Gain Weight Overnight?
For anyone trying to lose or maintain weight, seeing the number on the scale increase even the tiniest bit can be disheartening.
However, fluctuations in weight from day-to-day are not unusual. 45-75% of our body mass is water, after all. If you weighed yourself every hour, you would see shifts on the scale all throughout the day. Therefore, it’s important to keep the time of day you are stepping on the scale in mind and the many other factors that can lead to a slight change in weight.
Firstly, don’t panic. Unless you consumed an excess of close to 17,500 calories the day before — you won’t have gained 5 pounds of fat overnight.
These extra pounds can be traced back to many factors, the biggest being fluid retention and digestion. You’ve probably heard the term “water weight”, and this is most commonly the culprit for overnight weight increases.
Fluid retention can be a side effect of high sodium intake, medications, menstruation, muscle repair, etc. Higher intakes of sodium can cause our body to retain excess water, with the goal of balancing salt/water levels, then excreting the excess sodium in the urine. This is a natural regulatory process in the body that helps maintain ion and fluid balances and overall homeostasis. It sounds counterintuitive, but by drinking more water our body can efficiently get rid of excess fluid and flush any excess sodium. For more information, read our blogs covering everything you need to know about electrolytes and drinking too much water.
Another reason, we may not have fully digested (and excreted) everything we ate or drank from the day before. This is especially true if it was a “later-than-normal” dinner or a high fiber meal. Most foods can take anywhere from 24-72 hours to make their way through the whole digestive system—fiber having a longer transit time and higher water retention. So, if you haven’t had a bowel movement for several hours, this can easily disguise itself as a spike on the scale.
As you can see there’s several factors that can spike your weight. So, don’t sweat it if you step on the scale and the numbers went up overnight! Keep your routine – and the momentum you’ve been building – going and your weight will trend back to normal in no time!