I've been eating 85/15 Paleo for about 3 months and really appreciate the results. However, I've started to lightly spot in between my periods. I'm not, and have never been, on birth control; 25 years old; have never been pregnant; and I crossfit about 4 times a week. There are no cramps associated with the spotting, and it lasts anywhere from 4-8 days. I'm confused as to what's going on with my body and whether or not I should be concerned.
Ditto on what Dragonfly said.
If you are losing weight, your hormones, especially estrogen can elevate temporarily and overwhelm the signals from the other reproductive hormones, and that can do all sorts of weird stuff to your cycle. 4-8 days of extra bleeding every month would make me want to check with a doc just to make sure I was good on iron if nothing else.
Some ideas you could research, so you aren't just sitting there worrying until you can get in to see a gyno (you are emailing or calling your doctor right now, right?):
There is something called DUB (dysfunctional uterine bleeding) where part of the uterine lining thinks you are at a different part of your cycle than the rest of it.
Fibroids can cause spotting and bleeding anytime during the month.
If it is just past mid-cycle every month there is something called luteal phase defect that can happen when hormones get out of whack and the progesterone bump gets overwhelmed by estrogen. You can test this one by taking your temperature every morning, if it doesn't stay slightly elevated between ovulation and menstruation this could be the issue.
Bleeding can sometimes normally happen during ovulation, but 4-8 days sounds like either a cyst ruptured or you have something else going on.
And if this is the first time it has happened, it could be implantation spotting, so if no period in a few weeks a pregnancy test would be warranted.
I have absolutely no idea how diet might affect periods. What I would say, though, is that seeing your gynecologist would seem the most prudent thing--it's entirely possible that the spotting and the diet change are completely coincidental, and even if not maybe he/she can explain what's going on.
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