I agree with harrypotterrocks, your sodium intake is a huge factor with water retention. Alcohol is known to cause problems there too. And you'd have to be eating an insane amount of calories (3500 extra calories for 1 extra pound) to gain that much weight. Also, it may not be time of the month for you, but I always retain when I ovulate as well. All the hormones mess with me and there's only two weeks in the month I can get a non depressing weigh in. (Deep sigh...

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