I've been LCing on and off for about a year. When I first started, my periods became irregular and it drove me nuts. (I'm not taking any BC pills/hormones.)

Disruption of normal cycles seems to be one of the negative side effects of low carbing - but in the end I think it's all worth it. (My other side effects were losing massive amounts of hair - it eventually stopped - and big black circles under my eyes.)

My weight will also go up and down 4 or 5 pounds day-to-day, which is why I only weigh myself once a month or so. I don't even own a scale; I go to the grocery store.

The battle to control our weight isn't in the day-to-day details - it's what we're at in six months, a year from now. If I come off Atkins and gain a few and then decide to get my ass in line and stick with it again, I know that in a year I'll still be thinner, even if I'm not thinner today . Trust me, low carbing works.