Why Do I Lose Weight Over Night?

Weight loss at night is primarily the result of water loss. Respiration and perspiration are the culprits here, accounting for as much as 80 percent of weight lost over night. So if you’re wondering how much moisture you burned off last night, do the math. If your weight was down 3lbs from the night before, you lost a little over a liter of water.

Dieters often weigh themselves in the morning and at night. And while I’m all for tracking your results, this system can be unnecessarily disappointing if you don’t understand what’s happening. For instance, it’s not unusual for me to hear a complaint like this: Yesterday, all I ate was a couple pieces of toast, a cup of yogurt and a small salad. But my weight was up 4lbs by the time I went to bed! How is that possible?

If you’re tracking your weight in the morning and at night, you have to remember to not only consider the calories you’re consuming, but also the weight of the food and drinks. That salad may have only had several hundred calories, but who knows how much it weighed. And when you consider you’re probably drinking 60-100oz of water per day, it’s easy to see where a weight increase from morning to night would be likely, even on a restricted diet.

So my recommendation is to find a consistent time to weigh yourself. The rule of thumb is first thing in the morning. And though I’m all for weighing yourself every day, remember it’s the week to week number that counts. And the more of those weeks you can string together while keeping your weight down, the less likely it will be for you to gain the weight back.

Your body wants nothing more than to stay the same. So legitimate long term weight loss is a tough undertaking. But once the pattern starts, and you learn what affect different foods will have on your weight from day to day, you’ll be able to adapt your diet to maximize your results. And if you ever need a little advice or moral support, just let me know.

Arek Long  MA, CSCS

This entry was posted on Wednesday, January 25th, 2012 at 12:29 am and is filed under Articles. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.