My HormonologyI’ve gotten a bunch of emails recently from Hormonology fans with the same problem: During the middle and end of their period in their Week 1, they feel like PMS returns. They say they have aches, fatigue, foggy-headedness, the blues and/or irritability rather than the happy mood, increasing energy and decrease in pain that rising estrogen on these days of their cycle should be triggering.

If you’re bothered by similar PMS-like symptoms toward the end of your period, here’s what could be the problem: low iron. As you bleed during menstruation, iron levels drop. And research shows that even a slight dip in this key mineral that sends energizing oxygen throughout the brain and body can cause symptoms that mimic PMS.

Luckily, fixing the problem is easy: Simply eat more foods rich in iron (such as dark, leafy greens, dried apricots, iron-enriched cereal, beef, poultry and egg yolks). Or take a daily iron supplement (18 mg. for women ages 19 to 50; 14 mg. for women ages 14 to 18). By keeping your iron levels from dipping, you’ll dodge this “post-PMS” and enjoy your Week 1 far more!