I lost about 20 lbs these past few months--I know, drastic loss, I think it was from going vegan, but I'm at a health weight now, if at the lower end of the spectrum of healthy weight. However, I haven't had a period since last December, but it started happening before I lost the weight. I've been eating more now, more healthy fats and such (nuts, avocados, etc.), and it's been about a month. One thing I noticed is that I was cramping a bit last week, and this week I've been breaking out on my face (which doesn't usually happen unless I'm premenstrual).
My nutritionist said to perhaps cut back on my running--I run 4 miles nearly every day. I understand that I may have not been eating enough (unknowingly) for my activity levels. Now, I am, and I'm wondering if I need to cut back on running to regain my menstrual cycle, or if it will eventually come back as long as I'm eating enough?