How Much Estrogen Does A Man Have?

Written by Ben Bunting: BA, PGCert. (Sport & Exercise Nutrition) // British Army Physical Training Instructor // S&C Coach.

Estrogen, a steroid hormone i.e., a hormone derived from cholesterol, is one of the endogenous hormones produced in the body.

Hormones are molecules that act as chemical messengers and endogenous refers to molecules produced by the body.

Most of the hormones are produced by specialized organs in the body called glands while some are produced by various tissues like adipose or fat tissue. 

Female Sex Hormone

Estrogen, also called the female sex hormone, is primarily produced in the ovaries.

Secondarily, it can be produced from the brain, adrenal glands, bone, and testes as well. The most significant role played by estrogen is its role in females.

From developing secondary sexual characteristics such as breast enlargement to sustaining the fetus estrogen helps carry out numerous functions.

However, as mentioned above and contrary to the normal understandings, female sex hormones are also found in men but lower quantities and for different functions. 

There are three forms of estrogen produced by the body:

• Estradiol – the predominant form.
• Estriol – mainly produced during pregnancy.
• Estrone – found in higher quantities in post-menopausal females.

In this article, we will look at the importance of female sex .ormones in both genders. Moreover, we will go through some differences between estrogen and other similar steroid hormones (progesterone and testosterone). 

What does estrogen do?

The human body produces various estrogen formulations and the most produced one is estradiol.

Being a steroid hormone, it freely passes the cell membrane of various cells and bind to a receptor. The estrogen-receptor complex subsequently goes to the nucleus (the brain of the cell) activating or deactivating certain genes (codes).

Eventually, several proteins are produced that carry out the estrogen-specific effects. Now let’s look at its effects on the female and male bodies separately.

Estrogen effects on women

Estradiol is the primary hormone that gives females their specific characteristics. About 80% of the estrogen in females is produced in the ovaries.

From the onset of puberty and menarche, which is the onset of the menstrual cycle, sex hormones stimulate the body in many different ways. Some of the key effects of estrogen include:

• The onset of menarche – while the exact mechanism of how menstruation starts isn’t understood, estrogen levels tend to increase before and during menarche.
• Growth of the uterine lining – estrogen is the primary hormone necessary for the growth of the endometrial lining that sheds every month during periods.
• Breast enlargement – this effect of estrogen is seen during puberty and pregnancy.
• Making the skin thicker and warmer – the reason for female skin to be softer and warmer is due to the stimulation of new blood vessels and skin cells. The effects of estrogen might be responsible for some anti-acne effects on the skin.
• Lubrication of vagina and sexual desire – higher estrogen levels promote vaginal health, lubrication during sex, and the desire for sexual intercourse (the reason why it is called female sex hormone).
• Maintaining bone strength – estrogen works as a bone-protective hormone i.e., it reduces the resorption (breaking down of bone) and promotes bone health.
• Cardiovascular effects – estrogen, surprisingly, increases the amount of good cholesterol (HDL) in the body and lowers bad cholesterol (LDL). This is the reason why pre-menopausal women tend to have fewer cardiovascular conditions e.g., atherosclerosis, than men.
• Helps maintain ovaries and fertility – regular menstruation and fertility are promoted by estrogen.

Are estrogen and progesterone the same?

Progesterone is another steroid hormone with similar, female-specific effects, similar to those of estrogens.

But they are two different hormones with varying functions. Briefly speaking, estrogen is the predominant female-sex hormone and progesterone carries out functions like maintaining the uterine lining in the second half of the menstrual cycle, maintaining nutrition for the fetus in the uterus, promoting the growth of the breast tissue.

Simply put, progesterone is primarily responsible in females for the promotion of pregnancy. It prevents uterine contraction and promotes the thickening of the endometrial lining. 

Estrogen in Men

You might be thinking that female sex hormones should have no role in men. This name doesn’t correctly depict the role of estrogen in men.

The major pathway for estrogen synthesis in males is the conversion of testosterone.

Testosterone is converted to estrogen by the enzyme aromatase. Testes account for around 20% of the circulating estradiol in males and the rest comes from the brain, penis, and adrenal glands.

What does estrogen do to a man?

The hormone carries out functions like modulating libido or sexual desire, spermatogenesis, and maintaining fertility. Here are some facts about estradiol’s role in the male body.

1- Development and maintenance of sexual function

While it is true that testosterone is the main sexual hormone for men i.e., testosterone is primarily responsible for the masculine look (beard and muscles) and male reproduction, estrogen appears to be equally important.

Males indeed produce more testosterone relative to estrogen but the absence of estrogen has deleterious effects on the male sexual and reproductive system.

Research has suggested or rather proven that a balance between testosterone, estrogen, and progesterone is crucial for the development of testes during puberty and also for the production of sperm throughout adult life.

For a healthy reproductive system, certain systems need to work properly including the hypothalamic-pituitary axis, the testes, and penis.

The American Physiological Society advocates the fact that estrogen is produced and critically important for the proper functioning of all the systems. 

The penile and testicular production of estrogen hints at the fact that a balance between estrogen and testosterone is necessary for maintaining libido and proper sexual performance.

Studies have shown that deficiency or impaired function of any of these hormones decreases male reproductive and sexual efficiency. 

2- Bone mineralization and epiphyseal closure

Previously, the mineralization, in other words, deposition of solid material in the bones and their growth in males was attributed to androgens (testosterone-like hormones).

However, current data suggest that estrogen has an equally important role in the development of skeletal structure during puberty and the following growing years.

Estrogen also helps close the epiphyseal plates.

These plates are non-mineralized parts of the bone that help in liner bone growth (length of the bone). Altered levels of estrogen during the developing years can have effects like weak bone structure and stunted growth. 

3- Maintaining fertility

As mentioned previously, estrogen is an important hormone in the development and production of sperms.

Sperms are produced by germ cells in the testes. These germ cells are stimulated mainly through testosterone but estrogen also plays a significant role, especially during pubertal years.

This role is solidified by the fact that men with estrogen deficiency were reported to have hypo-spermatogenesis (reduced sperm production), seminiferous epithelial atrophy (needed for sperm maturation), and spermatogenic arrest. 

Moreover, semen analysis of people with low estrogen or estrogen/testosterone imbalance revealed normal to severe oligospermia and/or immotile sperms. These findings are consistent with the fact that estrogen is required by males to have adequate sperm growth and maintain fertility. 

High-levels of estrogen in Men

The above discussion shows the importance of estrogen in both males and females.

It should be noted, however, that it is highly critical for the levels of estrogen and testosterone to be within normal limits.

Excess of any of these hormones overpowers the other’s effect leading to various problems. 

Men having excess estrogen can experience various medical conditions that can impair their lifestyle. Some common side effects of having too much estrogen include:

• Gynecomastia – refers to the enlargement of breasts in males giving them a female-like appearance. This is one of the earliest and most noticed signs of excess estrogen in males. It can occur in both males and females.
• Erectile dysfunction – refers to the inability of having a (penile) erection or maintaining an erection during sexual arousal. This goes back to the discussion above that highlights the importance of a healthy balance between testosterone and estrogen. Having too much estrogen can also cause testosterone deficiency leading to erectile dysfunction.
• Infertility – high estrogen levels along with low testosterone levels have been associated with infertility in men
• Delayed puberty – excess estrogen levels can delay or prevent normal puberty in males. Estrogen promotes female-like traits instead of masculine features.
• Depression – this could be due to hormonal imbalance in the brain or secondary to other symptoms of estrogen excess. For instance, decreased libido due to high estrogen can, over time, lead to depression and anxiety (especially performance anxiety). 
• Short stature – these symptoms occur in kids who experience excess estrogen before their growth spurt. Estrogen causes the closure of epiphyses of the long bones impairing the linear bone growth leading to short stature.

Apart from these symptoms, excess estrogen might be associated with the following conditions in men:

• Diabetes
• Malignancy – estrogen producing tumor in the testes or adrenal gland
• Hyperthyroidism
• Liver cirrhosis

What causes elevated estrogen?

Finishing the dialogue on the relationship between estrogen and the male body, it is important to understand the potential mechanism for high levels of female sex hormones in men. They include:

• Producing too much estrogen – this occurs due to factors like persistent stress, high-fat content in the body, or decreased muscle mass. These factors stimulate the production of estrogen.
• Inadequate removal of estrogen from the body – certain factors act to reduce the clearance of estrogen from the liver. They include excess alcohol use and liver problems as the liver is the primary organ for the disposal of the hormone. 
• Medication/drug-associated increase in estrogen levels – certain medications have estrogen-like effects. 
• Synthetic xenoestrogens – xenoestrogens refers to the estrogen acquired from the environment. Bisphenol A and phthalates are some of the xenoestrogens used in various products like plastic. These chemicals act like estrogens once they are inside the body and might increase these hormone levels.

Estrogen vs Testosterone

The simplest answer for this subtopic is the usually known one; estrogen is the female sex and testosterone is the male sex hormone.

They are both steroid hormones and act via a similar mechanism. We will highlight some prominent differences between the two and they are:

• Male secondary sexual characteristics – testosterone and other androgens promote the growth of secondary sexual characteristics like beard, deepened voice, pubic hair pattern in men, etc. Estrogen, on the flip side, does not promote these features. 
• Muscle and fat growth – testosterone supports muscle growth and increases protein synthesis throughout the body while fat tissue is supported by estrogen. Also, having more muscle promotes higher levels of testosterone needed to maintain that muscle mass while having more fat promotes higher estrogen levels.
• Erection – adequate testosterone levels promote a healthy and sustained erection but high estrogen levels can cause erectile dysfunction
• Bone growth – estrogen has a higher bone-protective effect than testosterone
• Cardiovascular effects – estrogen promotes cardiovascular health and keeps cholesterol down while testosterone can have some negative effects like higher testosterone might lower good cholesterol. It should be noted that testosterone doesn’t affect bad cholesterol levels. 

Conclusion

Estrogen, progesterone, and testosterone all have important biological manifestations in the body.

Testosterone is the main sex hormone in the male body but estrogen has equally important roles in men.

It has various functions in men like bone growth, promoting good cholesterol but the important function is to promote the development and maintenance of sexual organs and reproductivity in men. 

Men need this hormone along with testosterone for the development of testes and germ cell maturation and viability.

In later years of life, balanced levels of the two hormones promote spermatogenesis, healthy sexual drive and sexual organs (penis and testes), and fertility.

having an imbalance between the hormonal levels could manifest various problems like erectile dysfunction, infertility, poor sexual drive, poor bone health, and poor heart health. 

 

References:

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