At any given moment you can be carrying around 3-5 pounds of water-weight, stomach and colon content. So depending on your food and water intake, digestive transit time and waste elimination speed you can bounce up and down by 5 pounds or so daily. But yes, take it! Don't freak out if it is back tomorrow, that just means that what you ate today has not left your system yet. I have myself set to weigh once a week because I can't handle the stress of watching it go up and down!!