What happens to your body when you block estrogen?

April 09, 2020

What happens to your body when you block estrogen?

What happens to your body when you block estrogen?

Estrogen is a female hormone that affects every aspect of women's health. The compound supports good mental health, brain function, menstruation, and fertility. It's even possible that balanced estrogen slows Alzheimer's disease from starting. In most cases, blocking estrogen goes against your body's needs for the hormone, and any imbalance may cause minor to serious side effects.


Although in certain circumstances, blocking estrogen is necessary to prevent breast cancer growth and gynecomastia (breast tissue growth) in men. The same chemical responsible for critical bodily functions may increase breast cancer risk. (1) In this article, we'll look at what happens to your body when you block estrogen.

What are estrogen blockers?


Estrogen blockers are chemicals that prevent cells from producing estrogen. It’s a kind of hormone antagonist or antiestrogen used in hormone therapy. All this means is that it stops the production of estrogen.

When are estrogen blockers used?


According to the American Cancer Association, about 1 in 8 women will develop breast cancer in the United States. (2) Breast cancer cells use estrogen or progesterone for continued growth. Progesterone is another important female sex hormone and provides a balance for estrogen. 2 out of 2 breast cancers are hormone-dependent. If hormones play a role, the cancers either have receptors for estrogen or progesterone. Both make cancer grow and spread.


How do estrogen blockers work?


If the breast cancer cells have an estrogen receptor, then using estrogen blockers may be useful in reducing the cancer growth and used as a treatment after cancer has disappeared or been removed. Instead of attacking the cancer cells, the growth is cut off from its food supply.


Women may take estrogen blockers for 5-10 years after surgery to stop cancer from coming back. Sometimes estrogen hormone therapy begins before surgery.


How do estrogen blockers affect the body?

In the case of breast cancer growth, blocking estrogen production is necessary. However, if your body blocks estrogen on its own, you may experience severe side effects.

Menopausal symptoms


Menopause is a duration in a woman's life cycle when reproduction comes to an end. While hormone levels do decrease as women age, menopause causes estrogen to crash or fluctuate erratically. As a woman's body becomes accustomed to varying hormone levels, she may experience one or many of the following symptoms:


  • Hot flashes
  • Night sweats
  • Mood swings
  • Impaired cognition
  • Reduced sex drive
  • Insomnia
  • Vaginal atrophy (dryness)
  • Dry skin
  • Hair loss


Menopausal symptoms can happen for perimenopausal women (a stage before the onset of menopause) and post-menopause. Typical treatment for menopausal systems is hormone therapy. Replacing the missing estrogen has become controversial in the last few decades.


The World Health Initiative published a landmark study showing that hormone replacement therapy increased the risk of breast cancer. (3) However, new literature analyzing the results of the research indicates that the risk is only higher for those over the age of 70. (4)


Women usually experience menopause in their late 40s and early 50s. If you take estrogen blockers or your body is reducing estrogen naturally when you’re younger, you may experience menopausal symptoms, too.




Estrogen helps balance emotions and well being. Low estrogen levels may cause you to feel sad or even become depressed. Anxiety and depression affect millions of people, and reasons for the mental health conditions vary, but studies show that hormonal imbalance plays a vital role in maintaining a positive mood. (5)



Fertility rates for women decrease as women age. However, if you block estrogen during your productive years, it will affect ovulation and menstruation. Both critical for conceiving a healthy child. Estrogen levels increase as the ovaries prepare to release an egg during ovulation. Standards continue to rise to help with implantation in the uterus. Blocking estrogen impairs this crucial reproductive process. It can even cause irregular periods and stop menstruation altogether. (6)

Weight Gain


Blocking estrogen levels may result in gaining weight. In studies with lab rates with lower estrogen levels, they tended to eat more and exercise less. Research shows that low estrogen results in a lower metabolic rate. The metabolic rate is the amount of time it takes your body to convert food to energy. It also affects the amount of fat storage in the body. During menopause, it's common for women to gain weight more around their middle.

Joint and muscle pain

One common side effect of blocking estrogen in joint and muscle pain. (7) Using estrogen blockers or aromatase inhibitors to limit breast cancer growth may cause pain in the feet and ankles, hands and wrists, and other parts of the body. Roughly 46% of women prescribed estrogen blockers experience joint pain and muscles for about 15% of the time.

Weak bones


Women taking estrogen blockers may be at increased risk for osteoporosis. Estrogen helps build healthy bones, and low levels may make the bone porous and brittle. (8) Women diagnosed with breast cancer should have a bone analysis to determine if taking estrogen blockers puts them further at risk for osteoporosis. Women can use vitamin D creams to help boost levels of the sunshine vitamin.

How long can you block estrogen?


The amount of time it's healthy for blocking estrogen depends on your health. In some cases, women can block estrogen for months or even years. It may make the difference between living a life without cancer or worrying about going in remission.


If you suspect you need estrogen blockers or think your body isn't producing enough estrogen, make an appointment with your healthcare provider. Estrogen is a critical hormone in balancing many vital functions, including your overall well being.

  1. https://www.nationalbreastcancer.org/breast-cancer-hormone-therapy
  2. https://www.cancer.org/cancer/breast-cancer/about/how-common-is-breast-cancer.html
  3. https://www.womenshealth.gov/30-achievements/25
  4. https://cmajnews.com/2017/04/12/landmark-trial-overstated-hrt-risk-for-younger-women-109-5421/
  5. https://ww.webmd.com/women/guide/estrogen-and-womens-emotions#1
  6. https://www.healthline.com/health/menstrual-periods-heavy-prolonged-or-irregular
  7. https://ww5.men.org/BreastCancer/SideEffectsofAromataseInhibitors.html
  8. https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=34&contentid=26606-1