Are you taking any vitamins? I noticed that when I started taking a daily multivitamin and fish oil that my mood became noticeably more pleasant. Also, I read in women's health last month that taking calcium is supposed to help too. It helps to regulate your hormones (at least that's what I remember the article saying off the top of my head).

And if you have cut calories to the extreme, that will also make you really bitchy.

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