Hi Sharpei & welcome.
Sorry to hear this hasn't been very successful for you so far. It can take a number of weeks for your body to adjust to the changes and often much of the initial 'larger' weight loss reported is purely water weight. Perhaps you've not lost water, but 1lb of fat gone is a good thing
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Everyone's perception of overweight is different, could you please give us some indication as to how much weight you need to lose? Don't worry, we're not here to judge - just to help! We're all in the same boat (and are probably quite lucky it hasn't sunk
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)
How do you do your fasts? Do you do the original version or the 24 hour version as described by Mimi in the book? The latter was something of a mistake for them to even mention as it really doesn't seem to be effective due to the minimal calorie deficit it produces.
Before you started 5:2 were you on any other weight loss plan? Were you holding around the same weight or were you gaining?
If you were gaining, then you were probably over eating - so even 2 days of fasting, combined with your normal eating habits may not be enough to product much of a deficit. It may be that you are still overeating on your feed days. Have you calculated what your daily calorie needs are to maintain your weight and compared how you eat on your feed days with this figure?