Estrone: A Comprehensive Guide to Its Functions and Effects

Estrone (E1) is a steroid hormone classified as a weak estrogen and a minor female sex hormone. It is one of the three major endogenous (made in the body) estrogens, along with estradiol and estriol, which play essential roles in female sexual development and function. Estrone is mainly synthesized from cholesterol and is secreted primarily by the gonads, but it is also produced by adrenal androgens in adipose (fat) tissue (source).

Estrogen Overview

There are three primary types of estrogen:

Estrone (E1) is a steroid and a weak estrogen, classified as one of the three major endogenous estrogens alongside estradiol and estriol¹. Produced primarily in a woman’s ovaries and, unlike estradiol, also in fat tissue, estrone’s primary role is to act as a precursor to estradiol². The human body is capable of converting estrone into estradiol when needed³.

Estradiol (E2) is the biologically “active” form of estrogen. It’s the most potent and prevalent estrogen in the human body. It heavily influences the growth and function of the reproductive organs. Estradiol is predominantly produced in the ovaries and plays a crucial role in the menstrual cycle, as well as in the development of secondary sexual characteristics in females. In men, estradiol helps regulate bone health, libido, and the production of sperm.

Estriol (E3) is the weakest of the three estrogens and is primarily produced during pregnancy. The placenta generates estriol in high amounts for the fetus’s development and well-being. Estriol levels peak during the third trimester and decrease significantly after giving birth. It is also thought to have various anti-inflammatory and immune-modulating effects that can benefit both the expectant mother and the developing fetus. High levels of E3 are protective against breat cancer.

Throughout a woman’s life, the levels of the different estrogens change. Estradiol is the predominant estrogen in most of a woman’s life, while during menopause, the body continues to produce estrone but at higher levels. This shift in estrogen levels impacts various aspects of a woman’s health and well-being. Understanding the role of estrone and its relationship with other estrogens can help provide insight into the effects of hormonal changes on women’s bodies throughout their lives.

When analyzing hormone levels, medical professionals often use the estrone test to diagnose and work up cases of precocious and delayed puberty in females, as well as in some cases with males⁵. The test also helps in diagnosing and working up suspected disorders of sex steroid metabolism, such as aromatase deficiency and 17 alpha-hydroxylase deficiency⁵.

Functions of Estrone

Estrone in Men

In men, estrone plays a minor role in comparison to testosterone. However, it is still present in the male body and is mainly produced in the testes. Estrone is essential for maintaining a balance between estrogen and testosterone levels. An excess of estrone in men can lead to unwanted side effects such as gynecomastia and a decrease in sex drive, while low levels could potentially result in decreased bone density.

Estrone in Women

Estrone is more prominent in women, where it plays a crucial role in the female reproductive system. During a woman’s reproductive years, estrone levels typically fluctuate throughout the menstrual cycle. In the early stages of the cycle, estrone production is stimulated by the follicle-stimulating hormone (FSH). As the follicle matures, estrone production increases, peaking just before ovulation.

Post-menopause, the ovaries’ production of estrone significantly decreases, leading to a decrease in overall estrogen levels. However, adipose tissue continues to produce small amounts of estrone, which contribute to the maintenance of various physiological functions in postmenopausal women, such as bone density preservation and cardiovascular health.

Estrone and Hormones

Comparison to Other Estrogens

Estrone (E1) is a weak estrogen and a minor female sex hormone. It is one of the three major endogenous estrogens, alongside estradiol (E2) and estriol (E3) ¹. Estradiol is the most potent and predominant type of estrogen, playing a crucial role in the female reproductive system². In contrast, estriol is the least potent form of estrogen and is mainly produced during pregnancy³. While estrone is weaker in comparison to estradiol, it can convert to estradiol when the body requires a higher concentration¹.

Relation to Progesterone

Progesterone is another essential hormone in the female reproductive system⁴. It complements the actions of estrogen, primarily during the menstrual cycle and pregnancy. While estrogen helps in developing and maturing the reproductive tract, progesterone is responsible for maintaining a stable environment in the uterus, facilitating the implantation and sustenance of a fertilized egg⁵. Both estrogen and progesterone play crucial roles in maintaining hormonal balance, and any imbalance between them can lead to various reproductive health issues⁶.

Androgen

Androgens are considered male sex hormones, but they are also present in the female body in lower amounts⁷. Testosterone is the most well-known androgen, playing a vital role in male sexual development and function⁸. In females, androgens act as precursors to estrogen production, with testosterone and other androgens converting to estrone and estradiol in the ovaries and adipose tissue⁹. The balance between estrogen production and androgen levels is crucial in maintaining overall hormonal balance and reproductive health¹⁰.

Estrone Levels

Causes of Low Estrone (E1)

Many things can lower production of E1, including chronic stress, adrenal dysfunction, ovarian dysfunction, and decreased activity of the enzyme (aromatase) that helps convert E2 –> E1.

Causes of High Estrone (E1)

Many things can cause an increased level of E1.  They include:

• High BMI: Since E1 can be produced by fat cells, the higher percentage of fat cells a person has, the more E1 they can produce.
• Increased Conversion of E2 –> E1
• Impaired detoxification
• Supplements

Effects of Age on Estrone Levels

Estrone levels vary throughout a woman’s life, being influenced by age, menstruation, pregnancy, and menopause. In general, estrone levels are higher in premenopausal women and decrease with age, especially after menopause.

Estrone in Pregnancy

During pregnancy, estrone levels can significantly increase due to the increased production of estrogen hormones. This helps to maintain a healthy pregnancy and support the growth and development of the fetus. The rise in estrone levels is essential for various pregnancy-related functions, such as the development of the placenta.

Estrone in Menopause

As women approach menopause, the production of estrogen hormones, including estrone, decreases. This reduction in estrogen levels can lead to various symptoms commonly associated with menopause, like hot flashes, mood swings, and irregular periods source.  Estrone is the only estrogen found in any significant quantity in post-menopausal women.

High Estrogen Levels

High estrogen levels, including elevated estrone levels, can lead to a variety of symptoms and health issues. Some common signs of high estrogen levels are:

• Weight gain
• Bloating
• Mood swings
• Breast tenderness
• Irregular periods

It is essential to monitor and maintain balanced estrogen levels to avoid adverse health effects, such as an increased risk for certain cancers and problems with fertility.

Low Estrogen Levels

Low estrogen levels can also have negative health consequences. Estrone, being a moderately potent estrogen, plays a role in bone health, mood regulation, and reproductive health source. Symptoms of low estrogen levels may include:

• Fatigue
• Hot flashes
• Osteoporosis
• Mood swings
• Vaginal dryness

Proper management of low estrogen levels, including estrone, is crucial for maintaining overall health and well-being, particularly during significant life transitions like menopause or post-pregnancy.

Symptoms and Conditions Related to Estrone

Menopausal Symptoms

Estrone levels are typically higher after menopause. Low or high estrone can cause uncomfortable symptoms such as irregular bleeding, fatigue, mood swings or difficulty sleeping. When the body experiences a decrease in estrogen hormones like estrone, it can lead to common menopausal symptoms including hot flashes, fatigue, poor sex drive, and depression.

Reproductive Health Disorders

Higher levels of estrogen, including estrone, can cause irregular periods and may worsen conditions that affect a woman’s reproductive health. It is essential to diagnose the cause of high estrogen levels and recommend appropriate treatments to maintain the balance of hormones.

Uterine and Breast Cancer

Estrogen hormones, including estrone, play a role in the development of various cancers, specifically uterine and breast cancer. Elevated estrone levels may increase the risk, although not in all cases. Further research is needed to draw conclusive evidence regarding estrone’s impact on uterine and breast cancer.

Bone Health and Osteoporosis

Estrone also plays a critical role in maintaining bone health. Women who have low estrogen hormones, including estrone, may develop osteoporosis. As estradiol levels decrease with menopause, estrone becomes the primary estrogen hormone and is responsible for maintaining bone density. Ensuring adequate estrone levels is essential for the prevention and management of osteoporosis.

Diagnosis and Monitoring of Estrone

Estrone Testing Methods

Estrone levels can be measured using blood, saliva, or urine samples. When conducting a blood test, a sample is taken from the patient’s arm, and this sample is then sent to a lab for analysis to determine the concentration of estrone. Saliva and urine tests, on the other hand, require the patient to collect a sample at home, which is then sent to a lab for testing. Both blood and saliva tests are effective methods for measuring estrone levels and can provide accurate results when performed correctly. Urine tests are superior for measuring estrogen levels and metabolism.

Indications for a Test

Estrone tests may be ordered for various reasons, primarily in women experiencing menopausal symptoms or infertility issues. Additionally, estrone tests may be used to diagnose suspected disorders of sex steroid metabolism, such as aromatase deficiency and 17 alpha-hydroxylase deficiency. In older men, estrone tests can help monitor low-dose female hormone replacement therapy. A healthcare provider may recommend an estrone test based on a patient’s specific symptoms, medical history, and other relevant factors.

When monitoring estrone levels in blood or urine, it is essential to keep in mind that fluctuations can occur depending on factors such as the time of day the sample is collected and the patient’s age. Therefore, it is crucial to follow the healthcare provider’s instructions and guidelines when undergoing an estrone test to ensure accurate results.

Treatment and Management

Hormone Replacement Therapy

One option for managing high levels of estrone is Hormone Replacement Therapy (HRT), which involves taking medications containing estrogen and progestin. HRT can help replace the missing estrogen hormone and alleviate menopausal symptoms. However, it’s essential to consider the potential risks associated with HRT, such as increased chances of heart attack, stroke, blood clot, breast cancer, and dementia.

Lifestyle and Diet Changes

Making lifestyle and diet adjustments is an effective way to manage estrone levels. For example, since obesity can lead to increased estrone production, losing weight can help lower levels. Incorporating a balanced diet rich in fruit, vegetables, and whole grains may also be beneficial. Additionally, regular exercise can improve overall health and potentially reduce the risk of conditions associated with high estrone levels, such as breast and uterine cancer.

Medication and Supplements

Certain medications and supplements may help regulate estrone levels, depending on the underlying cause. For example, a doctor might recommend hormonal therapy for breast cancer or prostate cancer treatment which helps in reducing estrone levels by targeting its production or function.Suppressing estrone levels could be critical in these cases, as high estrone may promote cancer growth.

In conclusion, managing high estrone levels can involve a combination of hormone replacement therapy, lifestyle and diet changes, and appropriate medication and supplements. Consult with a healthcare professional to determine the best course of action for your unique situation.

Risks and Side Effects

Estrone is a type of estrogen hormone, which plays a crucial role in many functions of the body. However, there are certain risks and side effects associated with estrone, especially when used for hormone replacement therapy.

One of the primary concerns with hormone therapy is the increased risk of certain serious conditions. In the largest clinical trial to date, hormone replacement therapy that consisted of an estrogen-progestin pill increased the risk of conditions such as heart disease, stroke, blood clots, and breast cancer (source). The risks vary depending on factors such as age and duration of hormone therapy.

Estrone levels are typically higher after menopause, and fluctuations in its levels can cause uncomfortable symptoms (source). Some of these symptoms include:

• Irregular bleeding
• Fatigue
• Mood swings
• Difficulty sleeping

Moreover, the use of estrogen alone in patients with a uterus has been linked to an increased risk of endometrial cancer (source). It is essential to note that combining estrogen with progestin may lower this risk (source).

In summary, while estrone is crucial for the proper functioning of the body, it is essential to be aware of its potential risks and side effects, especially when considering hormone replacement therapy. Consulting with a healthcare professional is crucial to assess the suitability of such treatment for each individual case.

Frequently Asked Questions

What causes high estrone levels in females?

High estrone levels can be caused by various factors, including obesity, polycystic ovary syndrome (PCOS), and certain medications. Additionally, estrogen dominance might occur due to fluctuating hormone levels during perimenopause and menopause. Cleveland Clinic provides more information on the causes of high estrogen levels.

What are the effects of elevated estrone?

Elevated estrone levels can lead to a range of symptoms and complications, including irregular periods, bloating, mood swings, and a worsening of reproductive health conditions. In some cases, consistently high estrogen levels may increase the risk of certain cancers, like breast or endometrial cancer.

How is estrone different from estradiol?

Estrone and estradiol are both forms of estrogen, but they have distinct roles in the female body. Estrone (E1) is produced mainly in fat tissue and is the dominant estrogen in menopause, while estradiol (E2) is essential for reproductive and menstrual functions and is the main female hormone throughout most women’s lives. For more information on estradiol and estrone, visit Liv Health.

Can diet influence estrone levels?

Yes, diet can influence estrone levels. Consuming a balanced diet rich in vegetables, fruits, fiber, and lean protein sources can help regulate hormone levels. Limiting the intake of processed foods, high-fat dairy products, and alcohol can also help reduce excess estrone production.

What are the symptoms of imbalanced estrone?

Imbalanced estrone levels can lead to various symptoms, such as irregular periods, weight gain, fatigue, mood swings, sleep disturbances, and decreased libido. For an in-depth discussion of the symptoms related to high estrogen levels, you can refer to Cleveland Clinic.

How can estrone levels be regulated?

Regulating estrone levels typically involves managing the underlying cause, such as treating PCOS or adjusting medication. Maintaining a healthy weight, exercising regularly, and consuming a balanced diet can also contribute to balanced hormone levels. In some cases, your healthcare provider may recommend hormone replacement therapy or other treatments to help regulate estrone levels.