Tired, blue, anxious or foggy during and after menstruation?

My Hormonology

Tired, blue, anxious or foggy during and after menstruation?



  • Experiencing a down mood, fatigue, anxiety, troubled sleep and/or food cravings during or after menstruation? It may be due to low iron.

UPDATED August 19, 2022 (originally published February 6, 2017)—If you’re a fan of Hormonology, then you’ve probably already read that during the first half of your menstrual cycle–which spans the first day of your period through ovulation–you tend to feel happier, more energetic, more confident and mentally sharper day by day. You also get better sleep. And food cravings wane. This is due to rising estrogen. As the level of estrogen climbs toward its peak at ovulation, it creates beneficial changes in your brain and body that give you all of these positive effects.

Of course, there’s some variation from woman to woman: Depending on your sensitivity to rising estrogen, you may feel brighter and sharper just a few hours after the start of your period or it may take a day or two or even three to kick in. But, generally speaking, this hormone spurs more positivity at some point during  your period week. And at the very least, rising estrogen helps you feel better compared to your premenstrual phase.

But, what if it doesn’t? What if there’s no improvement during period week, and still no improvement in the week leading up to ovulation? What if instead of feeling upbeat, you get sad or anxious? What if instead of feeling energized, you’re flattened by fatigue? What if you have trouble sleeping? What if you have food cravings? What if it still feels like you have symptoms of premenstrual syndrome or premenstrual dysphoric disorder?

One key reason could be that your iron level is low.

Low iron = low mood and energy

During your period, your body sheds iron in your menstrual blood. This makes your body’s store of iron dip. And if your iron gets too low, it can trigger fatigue, sadness, anxiety or mental fogginess. Low iron is also a culprit behind lousy sleep. And it can cause food cravings.

Why? For starters, iron helps produce serotonin, an important brain chemical that helps regulate mood, sleep and food cravings.

Plus, this essential mineral helps add oxygen to the blood, which energizes your brain and body and helps them function at their best.

It doesn’t take a big drop in your iron level to trigger tiredness, sadness and other symptoms. Research shows that women whose iron is still above the range that’s anemic (an iron level that’s low enough to be considered a medical condition) can still experience side effects from a drop in iron during menstruation.1

The easy fix

Fortunately, getting your iron back to normal is fairly easy: During your entire cycle–not just during menstruation–either increase your intake of iron-rich foods (such as fortified cereal, lean beef, beans, tofu and leafy green vegetables) or take a multivitamin with iron.

It may take more than one cycle to see a difference. Often normalizing nutrients in your system can take up to three cycles, so patience is key.

Also important: Don’t overdo it: 18 mg. is all the iron a woman from the age of 19 to 50 with menstrual cycles needs daily. Taking more than through supplements to try to speed or enhance the results can be harmful.

Keep in mind that some people can’t metabolize iron correctly, so talk with your doctor before starting an iron regimen. You can learn more about iron here.

Bonus: Iron also reduces premenstrual symptoms

Want one more reason to keep your iron levels from dipping? A 10-year study of 3,000 women in the American Journal of Epidemiology shows that women who upped their daily intake of non-heme iron–which is iron from non-meat food sources, such as kidney beans, tofu and spinach–were up to 40% less likely to experience premenstrual symptoms.2

The researchers believe it’s due to the way iron helps produce serotonin–a brain chemical that gets low in your premenstrual days, contributing to irritation, depression and moodiness.

Tips for taking iron

Iron can be a tricky mineral for your body to absorb, which means you could be increasing your intake of iron-rich foods or taking iron supplements and still not seeing a difference in mood, energy, sleep or cravings. So, here are a few tips to get the most out of this mineral:

If you’re getting your iron from plant-based sources (such as spinach), pair it with a food rich in vitamin C (such as bell peppers) or an animal-based iron source (such as lean beef) since these help your body absorb more of this non-heme iron.

Some compounds in beverages, supplements, medicines and foods limit the absorption of iron in your system. So, wait two hours before drinking milk, tea, coffee or cocoa, taking calcium or antacids or eating eggs or whole grains when taking an iron supplement.

If you’re taking iron supplements, pair them with a full glass of water or food to avoid stomach upset.

Still feel anxiety after menstruation?

While one side effect of low iron is a racing heart and other anxiety symptoms, if you notice that you’re still experiencing anxiety after menstruation, it may be because you’re more sensitive to rising estrogen. The level of this hormone gets higher and higher during your Week 1 and Week 2 (the first half of your cycle), which can trigger more arousal in the brain and nervous system. In some women, this can lead to anxiety symptoms.

So, what can you do about it? If you realize you’re more sensitive to rising estrogen’s anxiety-triggering effect, have anxiety-busters ready to use on these days. For example, try deep, slow meditative breathing or moderate exercise, such as brisk walks. You can also use yoga, chamomile tea, relaxing visual imagery or listening to slow-tempo music. All are study-proven ways to calm you.

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(1) Paul Vaucher, et al., “Effect of iron supplementation on fatigue in nonanemic menstruating women with low ferritin: a randomized controlled trial”, Canadian Medical Association Journal, 184 (2012): 1247-54
(2) Patricia O. Chocano-Bedoya, et al., “Intake of Selected Minerals and Risk of Premenstrual Syndrome”, American Journal of Epidemiology, 177 (2013): 1118–1127

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