Estrogen Balance in Men

What is Estrogen?

Men and women have dominant levels of specific hormones in their body that play a role in a wide array of metabolic functions – testosterone for men and estrogen for women. Although each hormone is identified with a specific sex, both of them are found in men and women.

The estrogen family includes the following:

1. Estrone (E1) – E1 is found in fats and muscles.
2. Estradiol (E2) – E2 is responsible for the development of female secondary sexual characteristics and maintenance of reproductive health.
3. Estriol (E3) – E3 is only detectable in pregnant women.

In women, the hormone estrogen along with the other female hormone called progesterone play an integral role in menstruation and almost all functions of the reproductive system. In men, the hormone estrogen also has a role in maintaining sexual health. While the hormone testosterone is the primary regulator of sexual function in men, estrogen levels need to stay in balance with testosterone to prevent unpleasant symptoms that may affect overall quality of life.

What is the Normal Range of Estrogen Levels in Men?

In prepubescent male, the level of estrone is 0-16 pg/ml while estradiol is 0-13 pg/ml. In pubescent male, estrone level is 0-60 pg/ml while estradiol is 0-40 pg/ml. In adult male, the normal range of estrone is 10–60 pg/ml while 10–40 pg/ml for estradiol.

High Estrogen Levels in Men

High estrogen levels can cause men to develop the following health problems:

1. Infertility: The body needs estrogen in order to produce sperm. However, studies show that high levels of estrogen can negatively affect sperm quantity and quality. [1-4] Specifically, high estrogen impairs spermatogenesis (sperm formation) by decreasing the size of seminiferous tubules, an area in the testes where sperm cells mature. [5-8] In addition, another mechanism by which high estrogen causes infertility in men is that it dilutes the sperm entering the epididymis rather than being concentrated, which significantly affect sperm quality. [9] Studies even found that higher estrogen levels were associated with lower sperm count. [10-13]
2. Sexual dysfunction: High estrogen levels can affect a man’s ability to get and sustain an erection. Studies found that hormonal imbalances such as testosterone deficiency and high estrogen were associated with increased severity of erectile dysfunction. [14-19] This hormonal imbalance is also linked with a higher incidence of premature ejaculation and sexual disinterest. [20-21]
3. Gynecomastia: Gynecomastia is characterized by enlarged breasts in men. Studies show that higher estrogen levels cause more breast tissue to develop, resulting in noticeably large breasts. [22-33]
4. Increased fat mass: Estrogen can increase fat mass by promoting the accumulation of subcutaneous fat in the body. Therefore, high estrogen levels may also have an impact on body composition. Evidence suggests that high estrogen is associated with a higher incidence of obesity, higher body fat percentage, and increased body mass index (BMI). [34-39]
5. Prostate issues: Several studies found that men suffering from benign prostate enlargement or prostate cancer have higher blood levels of estrogen. [40-49]
6. Stroke: Abnormal blood clotting in the blood vessels of the brain is the primary cause of stroke. High levels of estrogen contribute to the formation of abnormal blood clots. [50] A study found that men with high blood levels of estradiol (greater than 34.1 pg/mL) had a 2.2-fold greater risk of stroke compared with those with lower estradiol levels. [51] Another study also found that middle-aged men with higher levels of estradiol had thick carotid artery walls which can increase their risk of stroke. [52]
7. Cardiovascular disease: High estrogen levels can also have a negative impact on heart health. A study reported that patients with a history of heart attack had significantly higher blood levels of estradiol compared to patients with normal coronary arteries. [53] A study also found that men with coronary artery disease had higher levels of estrone. [54]
8. Peripheral artery disease: This condition is characterized by partial or total blockage of an artery in your arm or leg, resulting in poor blood flow. Affected individuals usually suffer from cramping, fatigue, and pain. In a study of elderly men, high blood levels of estradiol have been found to be associated with a higher risk of peripheral artery disease of the lower extremities. [55]
9. Rheumatoid arthritis: This severe chronic inflammatory condition attacks your own immune system and mainly affects the joints. A study reported that men with rheumatoid arthritis had high blood levels of estradiol. [56] Other studies show that high estrogen levels were associated with increased C-reactive protein, a marker of systemic inflammation and rheumatoid arthritis. [57-59]

Low Estrogen Levels in Men

Estrogen deficiency in men can also lead to the following health concerns:

1. Osteoporosis: Estrogen has a significant role in bone formation. By promoting the activity of osteoblasts (cells that produce bone), this hormone promotes bone growth and repair. In aging men, studies found that low estrogen levels can increase the risk of osteoporosis and fractures. [60-74] These bone problems occur since estrogen deficiency is associated with increased bone breakdown. [75]
2. Cardiovascular disease: Estrogen deficiency can increase the risk of cardiovascular disease in men via different mechanisms:
3. Low estrogen accelerates programmed cell death of heart cells (cardiomyocytes) [76-78]
4. Estrogen deficiency reduces blood flow to the heart. [79-80]
5. It impairs cardiac mitochondrial function. [81]
6. It also impairs vasodilation (widening) of the blood vessels of the heart. [82-85]
7. Cognitive dysfunction: Low estrogen can negatively impact mental health since this hormone modulates brain chemicals (neurotransmitters) responsible for cognitive and emotional processes. [86] A study found that men with schizophrenia tend to have lower estrogen levels. [87] Studies also found that age-related decline in estrogen levels were associated with declines in learning and memory function. [88-90]
8. Elevated cholesterol levels: Estrogen has cholesterol-lowering effects. Therefore, a decline in this hormone can have detrimental effects on cholesterol levels. A study even found that there is a strong link between high low-density lipoprotein (bad cholesterol) and estrogen deficiency. [91]
9. Increased risk of death: In a study of 501 men with chronic heart failure, men with the lowest blood levels of estradiol were 317% more likely to die during a 3-year follow-up. [92] Similar results were seen in a study of elderly men where subjects with lowest blood levels of estradiol had higher incidence of deaths during a mean follow-up period of 4.5 years. [93]

The Importance of Balancing Estrogen Levels

Balanced estrogen levels are critical to optimal health. An abnormal increase or decrease in estrogen can put you at greater risk for a broad range of medical maladies.

A study published in the Journal of the American Medical Association (JAMA) found that men with the lowest estradiol levels were more likely to die during a three-year follow-up. [94] In contrast, men with balanced estradiol levels (21.80 to 30.11 pg/mL) had the lowest death rates.

Another study published in the JAMA investigated the effects of testosterone and estrogen on body composition, sexual function, and strength in men. [95] While testosterone administration in these subjects produced positive effects on various aging factors, the Doctors at Massachusetts General Hospital administered the estrogen-suppressing drug anastrozole at high doses. The doctors overdosed the study subjects with the medication to proclaim that the subjects need estrogen and testosterone. As a result, the subjects had abnormally low estrogen levels (1.0 to 2.8 pg/mL) which in turn led to adverse effects such as increased abdominal fat, decreased sexual desire, and erectile dysfunction.

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