The Importance of a monthly menstrual cycle and amenorrhea

Written By: intern Harley Cobb


There are many unique things about being a woman, and the menstrual cycle is something we should learn to love (okay maybe not that far) and appreciate. There is much more than meets the eye in this week-long, recurring event.


Throughout the menstrual cycle, roughly 28 days depending on the person, there are fluctuations of hormones in the female body. Without getting into the nitty-gritty science of it, estrogen, progesterone, and testosterone are the main reproductive hormones, and estrogen in particular provides a multitude of health benefits. Estrogen is not only important for the reproductive system, it also promotes thyroid, bone, and heart health!

  • Thyroid: Estrogen stimulates thyroid hormone precursors, and therefore promotes overall thyroid function as well as hormone and weight balance.

  • Bone: Estrogen plays a key role in bone metabolism and bone turnover/remodeling, reducing one’s risk for osteoporosis and bone breaks.

  • Heart: Estrogen promotes heart health with anti-inflammatory properties, promotes vascular function, and can even prevent plaque build-up in arteries


Amenorrhea is the absence of a menstrual period. This is caused by low body weight, rapid weight loss, hormone imbalances, PCOS, thyroid problems, and stress, and is often prevalent in those with eating disorders such as anorexia nervosa.


When we don’t consume enough food and/or exercise in excessive durations or frequencies, our bodies enter into a state of stress or even starvation mode. This stress causes our bodies to not feel safe or able to function properly. When our bodies don't feel safe, they delegate the scarce energy available to vital organs such as our heart, lungs, and brain-- not leaving enough energy for accessory systems such as the menstrual cycle. Because our reproductive system isn’t actually a vital process in the body, it is one of the first systems to “shut down” when the body does not feel like it has enough energy to fuel all systems in the body. This is why losing your period is one of the tell-tale signs of under-eating, over-exercising, and/or an eating disorder (**This is not a self-diagnosis. Please contact your doctor or medical professional to be properly diagnosed).


While not having a period may seem convenient, it’s actually causing more damage than we may think. 


As mentioned above, the hormones that play a role in a healthy menstrual cycle affect many other areas of the body as well. When we don’t have a period:

  • Thyroid: A lack of estrogen can lead to hypothyroidism, an overall reduction in thyroid function.

  • Bone: The bone remodeling system is imbalanced due to the lack of estrogen, leading to a decrease in bone development and increased risk for osteoporosis. 

  • Heart: The lack of estrogen can increase one’s risk for plaque build-up in arteries, leading to heart attacks and increased risk for heart disease as well.


When we don’t menstruate once a month (give or take a few days depending on your specific cycle length), our thyroid gland, bones, and heart all suffer. 


But there is good news! Restoration and recovery is possible.


On the flip side of the state that causes amenorrhea, recovering your period results from the body feeling safe, fueled, and nourished. This may look like increasing the amount of food consumed daily, decreasing the frequency or duration of exercise, and taking rest days. It’s important to work with a clinician to help individualize treatment in order to restore your period, promote heart, bone, and thyroid health, and reach an overall sense of wellbeing in your body.




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Diamandis, E. P. (2021, October 21). Hypothyroidism, Estrogen & Menopause: What’s the link?: ImawareTM. Hypothyroidism & Menopause. https://www.imaware.health/blog/hypothyroidism-and-menopause#:~:text=Estrogen%20is%20also%20responsible%20for,thyroglobulin%2C%20which%20reduces%20thyroid%20function . 

Murphy, E., & Kelly, D. (2011). Estrogen Signaling and cardiovascular disease - aha/ASA journals. AHA Journals. https://www.ahajournals.org/doi/pdf/10.1161/circresaha.110.236687  

Santin AP, Furlanetto TW. Role of estrogen in thyroid function and growth regulation. J Thyroid Res. 2011;2011:875125. doi:10.4061/2011/875125 



Natalie Grun