RAther than using a hard number per week - 2 lbs, 1 lb, whatever, I prefer to go by the guideline that bases your rate of loss on your current bodyweight.
In other words, you should expect to lose 1% of your bodyweight per week, on average. I weigh 161, so I expect to lose about 1.6 lbs a week.
But you also have to keep in mind the "on average" part. I know that the week of my period I won't lose weight - whether I lose fat or not, the scale will not move. I know, in fact that it will go up by 3-5 lbs the week of my period. I also know that the week after my period it will go down again. Sometimes it'll drop just the 3-5 lbs of retained water from my period, and sometimes it'll drop even more, if I've lost fat as well.
But on AVERAGE ... over a period of time, I can count on losing around 1.6 lbs a week.
At least until I drop more weight. And then my weight loss will slow again.
I try not to put a timeline on my weight loss ... not to say that I don't keep some mental goals (like, I'd like to lose 10 more lbs by the first of the year), but I don't really set them as hard goals - just something to motivate me as I go along.
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