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Beyond Pregnancy – The Effects of Progesterone on Mood, Gut Motility (Period Poops!), Blood Pressure, Metabolism, Hair, and Skin in Men and Women

Sport, fitness and exercise with a sports man and woman training and stretching during an outdoor workout


As explained in our last blog post about fertility, the word progesterone translates to “promoting gestation,” so progesterone is often thought of as a female hormone required for fertility and healthy pregnancy. While this is true, progesterone has many effects beyond pregnancy, and an ideal progesterone level supports optimal health in men and women of all ages.1

Progesterone affects blood pressure; metabolism, including blood sugar metabolism; mood balancing; gut health; and more.2 In women, progesterone is primarily synthesized by the corpus luteum in the ovary during the second half of the menstrual cycle (after ovulation), the adrenal glands daily, and the placenta during pregnancy. In men, progesterone (which is a precursor for testosterone production) is predominately produced by the adrenal glands and the testes.3

Progesterone is a sex hormone that is derived from cholesterol. The sex hormones include androgens, estrogens, and progestogens; Progesterone is one of the progestogen hormones.4 Progesterone is also a neuro-steroid since it is produced in the brain.2,5

This blog post and our next blog will explore the many effects of optimal salivary progesterone levels in men and women.


Woman and Man with Healthy Salivary Progesterone Levels on an Adventure

Progesterone and Mood

As neuro-steroids, progesterone and its metabolites, including allopregnanolone, modulate several neurotransmitter systems that affect mood, including the serotonergic, cholinergic, muscarinic, and dopaminergic systems in men and women.2,6

The serotonergic system affects many complex processes, including mood balancing, sexual behavior, stress responses, cognition, reward, learning, and memory. Research suggests progesterone increases the transmission of serotonin, affects the levels of the enzymes that metabolize serotonin, and modifies the serotogenic responsivity to serotonin-reuptake inhibitors. It is clear there is also a connection between progesterone levels and serotonin synthesis, and this connection could be why mood tends to be more balanced during pregnancy and portions of the menstrual cycle when progesterone levels are higher.2

Healthy Fertile Couple with Optimal Salivary Progesterone Levels Relaxing on Boardwalk with Skateboard on a Warm Summer Day

Progesterone and Gut Motility (Period Poops!)

Many women report that their bowel movements are looser and more frequent during their menstrual period, and this phenomenon is attributed to the effects of shifting progesterone levels during the menstrual cycle.

The red line in the graph below shows the significant shift in progesterone levels during a healthy menstrual cycle:

Example of a Healthy Menstrual Cycle with Robust Salivary Progesterone Levels During the Luteal Phase

Progesterone receptors are present in the smooth muscles of the gastrointestinal (GI) tract, so progesterone plays a role in GI tract motility. Research indicates progesterone exerts a relaxing or inhibitory role on the smooth muscle cells in the gut.7 Therefore, a higher progesterone level reduces the number and frequency of bowel movements in men and women.

This is why the lower progesterone levels present during the follicular phase (Days 1-13 in the graph above), which begins when the menstrual period begins, are associated with diarrhea in women. The monthly phenomenon is known as “period poops.” When progesterone levels are higher during the luteal phase (Days 14-28 in the graph above) of the menstrual cycle after ovulation, constipation is more likely to occur. The robust progesterone levels present during a healthy pregnancy are an underlying cause of pregnancy-associated constipation.7

Researchers are also beginning to investigate the effects of progesterone and other sex hormones on gastrointestinal conditions, such as Irritable Bowel Syndrome (IBS).8

Happy Fertile Couple with Optimal Saliva Progesterone Levels Smiling and in Love Under a Beautiful Blue Summer Sky

Progesterone and Blood Pressure

Overall, progesterone tends to have a relaxing effect on all smooth muscle cells that express progesterone receptors. In addition to relaxing the smooth muscle in the gastrointestinal tract, research has shown progesterone also relaxes uterine and vascular smooth muscle.3,7

Since progesterone relaxes the smooth muscles in blood vessels, there is speculation it might decrease blood pressure, but the relationship has not been studied adequately. Based on the minimal research performed, it appears the effects of progesterone on blood pressure might depend upon several factors. One study discovered that among men, a 2.738 ng/ml increase in progesterone was associated with a 0.557 mmHg decrease in diastolic blood pressure and a 0.541 mmHg decrease in mean arterial pressure. Similar results were observed in postmenopausal women, but this beneficial association was only clear in premenopausal women when educational attainment was considered. Also, elevated progesterone levels in men were associated with high blood pressure in the study; therefore, monitoring and maintaining optimal salivary progesterone levels is essential in men.9

Healthy Man and Woman with Optimal Salivary Progesterone Levels Hiking on a Cool Summer Day

Progesterone, Insulin, and Blood Sugar Metabolism

An elevated progesterone level can have significant effects on blood sugar metabolism, so consider speaking with your doctor about testing your salivary progesterone level to ensure it is optimal.

According to research, progesterone directly stimulates the islet cells of the pancreas to produce more insulin. Therefore, a high progesterone level can induce hyperinsulinemia. Furthermore, progesterone affects carbohydrate metabolism by promoting the storage of glycogen in the liver (which could increase the risk of developing nonalcoholic fatty liver disease (NAFLD)). Progesterone also induces the transcription of gluconeogenic (glucose-producing) genes and activates glycogen phosphorylase, an enzyme required for glycogen metabolism, to increase the blood glucose level.10

Non-invasive clinical studies performed during pregnancy illuminate a direct relationship between higher progesterone levels and gestational diabetes. Also, the results of an animal study showed pregnant animals treated with progesterone were more likely to develop insulin resistance when compared to the placebo group.10

Overall, the metabolic effects of progesterone on blood sugar metabolism are adaptations that support a healthy pregnancy but can potentially be harmful to those with exceptionally elevated progesterone levels. Thus, maintaining a healthy salivary progesterone level at all ages and life stages is ideal.

Friends with Healthy Saliva Hormone Levels Having Fun on a Warm Summer Day

Metabolism, Progesterone, and Melatonin

Progesterone has a thermogenic effect that increases core body temperature; and, therefore, overall metabolism. Study after study confirms a higher body temperature during the luteal phase in young fertile women when the progesterone level is higher.11 This is why women can track their core body temperature every morning to determine the timing of ovulation.11,12

Progesterone will even increase the core body temperature when it is administered to men, young women without a menstrual cycle, and post-menopausal women. The thermogenic effect of progesterone is evident at very low doses of only 5 mg of progesterone in men, but higher doses are more likely to induce a consistent thermogenic response.11

While the research is ongoing, the thermogenic effect of progesterone appears to be related to melatonin. Melatonin naturally reduces core body temperature to support healthy sleep. Circulating levels and patterns of melatonin production are similar throughout the menstrual cycle in women, in both the follicular and luteal phases. But, research shows melatonin appears to have a reduced hypothermic effect during the luteal phase.11,12

Researchers speculate a higher progesterone level may inhibit the nightly core body temperature-lowering action of melatonin in the luteal phase. When melatonin is administered to healthy women during the day in the follicular and luteal phases, core body temperature decreases during the follicular phase but not during the luteal phase, suggesting progesterone must affect the hypothermic action of melatonin.11

To further support the role melatonin plays in the thermogenic effect of progesterone, a recent clinical study demonstrated that light exposure during the follicular phase suppressed melatonin production (as expected), which resulted in a core body temperature similar to that of women in the luteal phase.11

The consequences of changes in metabolism and core body temperature during the menstrual cycle are not yet well understood. Research to date has illuminated correlations between core body temperature, cognitive performance, sleep quality, and heart rate. Studies show the poorest cognitive performance coincides with lower body temperature, low progesterone levels, and the follicular phase of the menstrual cycle.11

Some studies have noted a small reduction in REM sleep in the luteal phase of the menstrual cycle. This phenomenon could be related to the effect progesterone has on melatonin and the higher core body temperature during the luteal phase of the menstrual cycle when the progesterone level is higher. An increased heart rate is also present during the luteal phase of the menstrual cycle, and researchers speculate the increase could be secondary to the boost in core body temperature and metabolism.11

Future research will continue to explore the effects of progesterone and melatonin on core body temperature, metabolism, and other physiologic processes in the body.

Two Happy Friends with Optimal Salivary Progesterone Levels

Progesterone, Hair Loss Prevention, and Healthy Skin – Can Stress Cause Hair Loss?

An optimal progesterone level supports healthy skin and hair. Research shows the use of micronized progesterone in postmenopausal women clearly offers anti-aging skin benefits.13

Progesterone also influences the hair follicles via both direct and indirect mechanisms. The presence of a healthy progesterone level reduces the excessive secretion of a hormone called Luteinizing Hormone (LH) from the pituitary gland. LH acts to increase androgen production in men and women. If androgen production increases too much and results in a high salivary dihydrotestosterone (DHT) level, the elevated free DHT level can cause hair loss.14

At the level of the hair follicle, progesterone directly decreases the conversion of testosterone to dihydrotestosterone by inhibiting the 5-alpha reductase enzyme.14 Chronic stress can contribute to hair loss because the adrenal glands produce progesterone. Low progesterone levels are associated with the excessive production of DHT within the hair follicles leading to hair loss.13-15

Here is a depiction of excessive DHT production in a female with chronic stress and hair loss:


Expanded Androgen Pathway Panel - High Salivary DHT Level in a Woman with Chronic Stress, PCOS, and Hair Loss


Based on the available research, supporting optimal progesterone production and healthy salivary progesterone levels in men and women may be beneficial for many health concerns, including infertility, diarrhea, constipation, hypertension, insulin resistance, blood glucose dysregulation, mood balancing, hair loss, and skin concerns.

To support optimal progesterone levels, consider nourishing your adrenal glands with vitamins, minerals, and organic botanical extracts, including Ashwagandha.*

B-KalmPlexus is a unique formulation that includes B vitamins, magnesium, and Ashwagandha to support optimal adrenal function and balanced hormone levels.*

B-KalmPlexus is a unique formulation that includes B vitamins, magnesium, and Ashwagandha to support optimal adrenal function and balanced hormone levels

Flavo PlexC is a physician-formulated supplement that features vitamin C, magnesium, Ashwagandha, and potent antioxidants to support optimal progesterone production.*

Flavo PlexC is a physician-formulated supplement that features vitamin C, magnesium, Ashwagandha, and potent antioxidants to support optimal progesterone production

* This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.




Testosterone is considered the “elixir of life” and has been sought after for its rejuvenating properties for millennia. Testicular extracts from animals were used by the ancient Chinese and the Romans for men’s health. The idea and practice of optimizing hormone levels for health benefits became more widespread when the acclaimed scientist and endocrinologist Dr. Charles Brown-Séquard regularly injected himself with testicular extracts in the late 1800s to restore vitality.


Most of us think of melatonin as the hormone that is required for optimal sleep. While this is true, melatonin also has a variety of other beneficial effects beyond sleep. Melatonin is known to affect the immune system, bone health, fertility, mitochondrial function, and more. Since melatonin does have a profound impact on many different organs and tissues, it is important to test your natural melatonin levels and be mindful of them when thinking about supplementing with this fascinating hormone.


April is Stress Awareness Month, so let’s learn more about the stress hormone known as cortisol! While cortisol is known as the stress hormone, it is crucial for the optimal function of your body every day. In healthy individuals, cortisol levels naturally shift throughout the day in a pattern known as a diurnal rhythm.


If you could choose, would you rather spit into a tube or have a needle jabbed into your arm to measure your hormone levels? We suspect you would rather not get stuck with a needle, and you do have a choice! Saliva hormone testing offers many benefits, including painless collection in the comfort of your home at any time. Saliva hormone tests can help determine the underlying cause(s) of PMS, insomnia, anxiety, fatigue, infertility, migraines, weight gain, hot flashes, hair loss, and many other health concerns.


  1. Nagy B, Szekeres-Barthó J, Kovács GL, et al. Key to Life: Physiological Role and Clinical Implications of Progesterone. Int J Mol Sci. 2021;22(20):11039. doi:10.3390/ijms222011039
  2. Kolatorova L, Vitku J, Suchopar J, et al. Progesterone: A Steroid with Wide Range of Effects in Physiology as Well as Human Medicine. Int J Mol Sci. 2022;23(14):7989. doi:10.3390/ijms23147989
  3. Bulletti C, Bulletti FM, Sciorio R, Guido M. Progesterone: The Key Factor of the Beginning of Life. Int J Mol Sci. 2022;23(22):14138. doi:10.3390/ijms232214138
  4. Pompili A, Iorio C, Gasbarri A. Effects of sex steroid hormones on memoryActa Neurobiol Exp (Wars). 2020;80(2):117-128.
  5. Guennoun R. Progesterone in the Brain: Hormone, Neurosteroid and Neuroprotectant. Int J Mol Sci. 2020;21(15):5271. doi:10.3390/ijms21155271
  6. Szczurowska E, Szánti-Pintér E, Chetverikov N, et al. Modulation of Muscarinic Signalling in the Central Nervous System by Steroid Hormones and Neurosteroids. Int J Mol Sci. 2022;24(1):507. doi:10.3390/ijms24010507
  7. Alqudah M, Al-Shboul O, Al Dwairi A, et al. Progesterone inhibitory role on gastrointestinal motility. Physiol Res. 2022;71(2):193-198. doi:10.33549/physiolres.934824
  8. So SY, Savidge TC. Sex-Bias in Irritable Bowel Syndrome: Linking Steroids to the Gut-Brain Axis. Front Endocrinol (Lausanne). 2021;12:684096. doi:10.3389/fendo.2021.684096
  9. Shi J, Wei D, Wang L, et al. Serum Progesterone is Negatively Associated with Hypertension and Blood Pressure Indicators Among Men and Postmenopausal Women. Horm Metab Res. 2023;55(4):273-283. doi:10.1055/a-2024-0708
  10. Azeez JM, Susmi TR, Remadevi V, et al. New insights into the functions of progesterone receptor (PR) isoforms and progesterone signaling. Am J Cancer Res. 2021;11(11):5214-5232
  11. Baker FC, Siboza F, Fuller A. Temperature regulation in women: Effects of the menstrual cycle. Temperature (Austin). 2020;7(3):226-262. doi:10.1080/23328940.2020.1735927
  12. Su HW, Yi YC, Wei TY, et al. Detection of ovulation, a review of currently available methods. Bioeng Transl Med. 2017;2(3):238-246. doi:10.1002/btm2.10058
  13. Gasser S, Heidemeyer K, von Wolff M, Stute P. Impact of progesterone on skin and hair in menopause - a comprehensive review. Climacteric. 2021;24(3):229-235. doi:10.1080/13697137.2020.1838476
  14. Grymowicz M, Rudnicka E, Podfigurna A, et al. Hormonal Effects on Hair Follicles. Int J Mol Sci. 2020;21(15):5342. doi:10.3390/ijms21155342
  15. Thom E. Stress and the Hair Growth Cycle: Cortisol-Induced Hair Growth Disruption. J Drugs Dermatol. 2016;15(8):1001-1004.

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