top of page

Timing is Everything, Period.

Updated: Jun 20, 2023


Most women who have menstrual cycles know the constellation of symptoms before, during, and after their periods. But what else do we know about how hormonal fluctuations are connected to the rest of the body’s functions? Integrative medicine practitioners recognize the interconnection between the different body systems, and now researchers recognize this as well. We are beginning to get information through research studies on the differences in disease manifestation due to sex and hormones. Most importantly this comes down to each individual’s interplay between their circadian rhythm and hormonal rhythms, and the connection between the brain, the reproductive organs, and the rest of the body. For menstruating women, tracking cycles on apps and maximizing activities around follicular, ovulatory, or luteal phase has become popular. It might be beneficial to some menstruating females to consider this along with circadian rhythms when considering aspects of health and preventing disease. (Read my last blog on circadian rhythms

Here are some ways hormones can affect health issues, and research is growing in all of these areas. So yes, it’s ok to blame your hormones!

Diet, Weight Loss, and Diabetes

It is well-known now that energy intake and expenditure changes through the menstrual cycle. Many of us get cravings to eat certain food around certain times, this also has to do with nutrients as well as calories. A 2016 study showed that a weight loss program designed around menstrual cycles to adapt to metabolic changes and food cravings helped a group of women lose 10 pounds more over 6 months compared to a traditional weight loss program. Though not statistically significant due to a large dropout rate, it was the first study to ever to show that menstrual cycles can affect weight loss. Estrogens and progesterone do affect glucose tolerance, insulin sensitivity, and gastric emptying and therefore hormonal fluctuations can be worse for diabetics.

Exercise and Performance

Athletes are particularly affected by menstrual cycles and this area of research continues to grow. Research scientists state that strength training is best done in the first half of the menstrual cycle, because of adaptation and recovery.


Most studies show that women experience sleep issues right before their periods and at onset of their periods. Some feel the insomnia during this time has to do with a lack of synchronization between temperature and sleep-wake rhythms during the luteal phase. Some women have been shown to be very sleepy for about one week before their menses due to higher levels of progesterone, this is now called menstrual related hypersomnia.

Autoimmune Disease

Studies show that estrogen and progesterone levels affect T cells, B cells, and monocytes, all immune cells that regulate various immune functions. Worsening of autoimmune diseases, like lupus and multiple sclerosis, during the second half of the menstrual cycle has been reported, and menstrual irregularities are present in these populations. How hormones interface with the immune system is still being explored. There is even information about COVID immunity and menstrual periods now!


More women have asthma, cystic fibrosis and chronic obstructive pulmonary disease, and there are higher reports of hospitalizations premenstrually. Estrogens impact immune function and progesterones are smooth muscle relaxants of the bronchioles.

Cardiac Disease

Estrogens and progesterones affect transporter molecules and ion channels action in the heart. Research has shown that women have higher resting heart rates compared to men, this seems to be related to circulating androgens. In fact, if certain medications cause a side effect of an irregular heart rhythm, it may be due to the added effect of estrogens and progesterones.

This is just a very brief overview of some of the health issues related to menstrual cycles. More to come on pain, mental health, and fertility!

Please reach out to Dr. Milan for a more integrative approach to your healthcare.


Baker FC, Driver HS. Circadian rhythms, sleep, and the menstrual cycle. Sleep Med. 2007;8(6):613-622. doi:10.1016/j.sleep.2006.09.011

Bailey M, Silver R. Sex differences in circadian timing systems: implications for disease. Front Neuroendocrinol. 2014;35(1):111-139. doi:10.1016/j.yfrne.2013.11.003

Geiker NR, Ritz C, Pedersen SD, Larsen TM, Hill JO, Astrup A. A weight-loss program adapted to the menstrual cycle increases weight loss in healthy, overweight, premenopausal women: a 6-mo randomized controlled trial. Am J Clin Nutr. 2016;104(1):15-20. 

Oertelt-Prigione S. Immunology and the menstrual cycle. Autoimmun Rev. 2012;11(6-7):A486-A492. doi:10.1016/j.autrev.2011.11.023

Oleka CT. Use of the Menstrual Cycle to Enhance Female Sports Performance and Decrease Sports-Related Injury. J Pediatr Adolesc Gynecol. 2020;33(2):110-111. doi:10.1016/j.jpag.2019.10.002

Shechter A, Varin F, Boivin DB. Circadian variation of sleep during the follicular and luteal phases of the menstrual cycle. Sleep. 2010;33(5):647-656. doi:10.1093/sleep/33.5.647

Thackray AE, Deighton K, King JA, Stensel DJ. Exercise, Appetite and Weight Control: Are There Differences between Men and Women?. Nutrients. 2016;8(9):583. Published 2016 Sep 21. doi:10.3390/nu8090583

32 views0 comments


bottom of page