I agree it can be both the scale and salt intake. I know my scale I weigh myself many times and which ever number comes up 3 times in a row is what I go with as my weight. I know it sounds strange. But I also know that alot of foods that I eat have more salt it them ie I made chicken souo from scrach last night and I belive it had a little too much salt in it. So I am retaining it today. Stacey