In the female, estrogen is produced chiefly in the ovaries, however, fat cells, breast tissues, adrenal glands, placenta, etc can also produce small amounts of estrogen. This hormone performs a lot of good functions in the body, but other hand, it is also associated with the growth of many tumors in the body. So it's more like a two-edged sword.
By Belinda Hankins Miller from U.S.A, CC BY 2.0, Wikimedia
In this post, I will discuss the normal functions of this hormone, estrogen, the cancers that are associated with it, the different conditions that predispose individuals to the bad sides of this hormone, and most importantly, how to prevent them. Please do stay till the end.
NORMAL FUNCTIONS OF ESTROGEN
This chemical messenger primarily helps in the development of the female secondary sexual characteristics like the breasts, feminine shape, growth of pubic hairs, etc. It also works with progesterone to control the menstrual cycle and prepare the female for reproduction by the growth of the inner lining of the womb (endometrium), improve uterine growth, ovulation, etc.
The concentration rises during puberty and declines after menopause. Apart from the reproductive roles listed above, estrogen also plays important roles in other systems of the body. Estrogen affects brain function, mood, and memory. It also affects bone formation and muscle mass (musculoskeletal system), heart and blood vessels, body fluid balance, blood pressure, sugar and fat levels, as well as even the skin.
Estrogen acts by binding to some specific proteins in the body called estrogen receptors which are located throughout the body. So when there is a need for estrogen, it is carried in the blood to that tissue where it binds to the estrogen receptors in that tissue to achieve the desired effects. This has been beneficial to the normal growth and development processes in the body.
However, certain cancers have been shown to also contain these estrogen receptors, and therefore, estrogen when in high concentration is carried in the blood to these abnormal tissues, where it binds to the estrogen receptors in them and cause the growth of those abnormal (cancerous) cells and tissues.
This is dangerous to the body and has been found in the cause of many tumors like breast cancer (abnormal and uncontrolled growth of the cells and tissues of the breast), uterine fibroids (abnormal growths in the uterus), endometrial cancer (which occurs in the inner lining of the womb), and Ovarian Cancer (where the ovarian cells grow and multiply uncontrollably).
By Cancer Research UK, CC BY-SA 4.0, Wikimedia
This can also occur when estrogen occurs in a higher concentration than progesterone. Estrogen works together in a regulated balance with another chemical messenger called progesterone. When this balance is altered and estrogen level gets higher than progesterone, this estrogen dominance also predisposes the body to these tumors.
Let us look at those conditions that predispose one to a high level of estrogen or an unopposed action of estrogen.
Early age of first menstrual period(menarche).
The average age at which a female sees her first menstrual flow is at the age of 12 to 13 years. However, in some individuals, this appears at an earlier age before 12 years. Women who have early menarche have been found to have a higher level of estrogen in their blood than those who had menarche at a later age. This high level of estrogen constitutes a risk factor for these estrogen-dependent tumors.Use of estrogen-based oral contraceptive pills.
These contraceptive pills contain synthetic forms of estrogen and therefore increase the concentration of estrogen in the blood. This aids the growth and development of these estrogen-dependent cancers.Use of hormone replacement therapy
As I stated above, the concentration of estrogen drops during menopause. This causes some severe symptoms in some women. Hormone replacement therapy is a treatment usually given to these menopausal women to boost the low level of estrogen and ameliorate their symptoms.
But because this hormone replacement therapy contains estrogen, it increases the concentration of estrogen in the blood and constitutes an increased risk of these cancers.
- Late age at first pregnancy and lesser number of full-term pregnancies (parity)
Those who have had a full-term pregnancy at an earlier age and those who have an increased number of full-term pregnancies have been found to have a reduced risk of breast cancer while those who have a full-term pregnancy at a later age or a lesser number of full-term pregnancies are at increased risk.
This is because full-term pregnancy makes the breast cells to be more mature and have a more coordinated growth than immature breast cells that are more likely to grow uncontrollably (breast cancer).
- Lesser period of breastfeeding
During breastfeeding the level of this hormone estrogen remains low while the level of prolactin rises. So the longer a woman breastfeeds, the longer time of low estrogen level which is beneficial and protective.
Those who breastfeed for a shorter duration don't benefit from this prolonged low estrogen level and are at increased risk of these cancers.
Late age at menopause
Since the level of estrogen declines at menopause, those who have late menopause after the age of 55 years have longer exposure to this hormone and are at increased risk too.Obesity
Fat cells also secrete estrogen and those who have larger fats and adipose tissues have a higher concentration of estrogen and increased risk of cancer, especially in post-menopausal women.Other conditions like Polycystic Ovarian Syndrome (where there are multiple pockets of fluids in the ovaries), Excessive stress, liver problems, etc have also been found to elevate the estrogen level in the blood.
By Yapa Wijeratne - Own work, CC BY-SA 4.0, Wikimedia
TREATMENT
When a high level of hormone is detected in these conditions through a hormone analysis, there are drugs used to reduce the level of hormones produced by the body. These are the Gonadotrophin-releasing hormone agonists and aromatase inhibitors. But the most important here is to prevent this high or unopposed estrogen action as prevention is better than cure.
PREVENTION
So lets us talk about how to decrease the risk of these high estrogen effects.
- Prolonged breastfeeding is very helpful since the levels of estrogen remain very low throughout the breastfeeding period. Exclusive breastfeeding is usually recommended which entails giving the baby only breast milk for 6 months and then adding water and other foods afterward while the breastfeeding continues for up to 2 years.
Cancer researchers found that for every 12 months a woman breastfed, her risk of breast cancer decreased by 4.3%.
So the importance of breastfeeding to both the baby and the mother cannot be overemphasised.
By USDA, Public Domain, Wikimedia
When using contraceptive pills or hormone replacement therapy, it is also very important to consult your doctor to advise you on the best available options most suitable to you.
Maintaining healthy body weight is also important as obesity is a culprit in these elevated estrogen conditions. So it is important to exercise regularly and eat a healthy diet.
It is also important to limit excessive alcohol intake and stress. Good sleep and a healthy lifestyle are always beneficial.
In conclusion, estrogen is a very important hormone in the body that carries out very key functions in both males and females. It works hand in hand with other hormones like progesterone to regulate some body's vital functions.
However, when the estrogen becomes in excess in the blood or acts unopposed, it can be very dangerous to the body and leads to many cancers of the breast, ovary, and uterus. The knowledge of this has also been applied in the development of therapies for some of these cancers that have been found to be hormone receptor positive.
Therefore, we must watch out for this at all times and follow the preventive measures itemized here to stay healthy and stay away from these estrogen-dependent cancers.
Thanks so much for reading.
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