Estradiol (E2)

Primary female sex hormone

16/22Providers

Sex Hormones (FCategory

bone densityReference

Widely Available

16 of 22 providers

Reference Range

bone density

What is Estradiol (E2)?

Estradiol (E2) is the most potent and predominant form of estrogen in the body, and it's critically important for BOTH men and women. In women, it's produced primarily by the ovaries and drives sexual development, menstrual cycle regulation, bone health, cardiovascular protection, cognitive function, and more. In men, estradiol is produced by aromatization of testosterone in fat tissue and other organs, and it's essential for bone density, libido, cardiovascular health, and brain function.

Here's what most people misunderstand:estradiol isn't just a "female hormone,"and testosterone isn't just a "male hormone."Men need estradiol for optimal bone density and cardiovascular health—too low is as problematic as too high. Similarly, women need testosterone for muscle mass, libido, and energy. The key is balance. In men on testosterone replacement therapy (TRT), excessive aromatization can elevate estradiol, causing gynecomastia (breast development), water retention, and mood issues. Conversely, blocking estradiol too aggressively with aromatase inhibitors can harm bone density and lipid profile.

Estradiol levels vary dramatically across the menstrual cycle in premenopausal women (low in follicular phase, peak at ovulation, moderate in luteal phase) and plummet after menopause. Postmenopausal women have estradiol levels similar to men unless on hormone replacement therapy (HRT). Optimal estradiol levels are context-dependent:cycling women should be tested on specific cycle days, while men and postmenopausal women have static targets.

Why Estradiol Matters for Longevity (Men and Women)

Bone density:Estradiol is THE most important hormone for maintaining bone mineral density in both sexes. Low estradiol=accelerated osteoporosis.
Cardiovascular protection:Estradiol improves endothelial function, raises HDL, lowers LDL, and reduces arterial stiffness (premenopausal women have lower CVD risk than men).
Brain health:Estradiol supports cognitive function, memory, mood, and may protect against Alzheimer's disease. Estradiol decline at menopause linked to cognitive decline.
Libido and sexual function:Optimal estradiol supports libido in both sexes. Too low OR too high impairs sexual function in men.
Metabolic health:Estradiol improves insulin sensitivity and body composition. Loss at menopause drives visceral fat accumulation.
Skin and connective tissue:Estradiol maintains skin thickness, collagen, and elasticity.

Optimal vs Standard Ranges

Range Type	Level	Significance
Optimal (Men)	20-40 pg/mL	Sweet spot for men. Higher levels (>50 pg/mL) may cause gynecomastia, water retention, mood issues. Lower levels (<20 pg/mL) harm bone density and lipids.
Optimal (Premenopausal Women - Follicular)	30-100 pg/mL	Early follicular phase (days 1-7 of cycle). Estradiol is low after menstruation, then rises.
Optimal (Premenopausal Women - Ovulation)	100-400 pg/mL	Midcycle (days 12-16). Estradiol peaks at ovulation to trigger LH surge.
Optimal (Premenopausal Women - Luteal)	80-200 pg/mL	Luteal phase (days 17-28). Estradiol is moderate;progesterone dominates in this phase.

Standard lab range: bone density

How to Optimize Estradiol (E2)

1. Optimal (Postmenopausal Women)

10-30 pg/mL

2. Without HRT, postmenopausal estradiol is very low (similar to men). HRT typically targets 40-100 pg/mL to relieve symptoms and protect bone/heart.

High (Men)

3. >50 pg/mL

Elevated estradiol in men. Causes gynecomastia, water retention, erectile dysfunction, mood swings. Often due to obesity or excessive TRT without aromatase inhibitor.

4. Manage High Estradiol in Men (if >50 pg/mL)

Aromatase inhibitors (AI):Anastrozole (Arimidex) 0.25-0.5 mg twice weekly reduces estradiol by blocking testosterone→estradiol conversion. Goal:bring E2 to 20-40 pg/mL. Caution:excessive AI use crashes estradiol, harming bones and lipids.

Weight loss:Fat tissue contains aromatase enzyme. Losing body fat reduces estradiol production.

Reduce TRT dose:If on supraphysiologic testosterone, lowering dose reduces substrate for aromatization.

DIM (diindolylmethane):100-200 mg/day from cruciferous vegetables may support estrogen metabolism. Modest effect.

5. Hormone Replacement Therapy (HRT) for Postmenopausal Women

Estradiol is the gold standard for menopausal symptom relief (hot flashes, vaginal dryness, mood, sleep) and prevention of bone loss and cardiovascular disease.

Transdermal estradiol (patch or gel):0.025-0.1 mg/day. Preferred route;avoids first-pass liver metabolism, lower VTE risk than oral.

Oral estradiol:0.5-2 mg/day. Convenient but increases clotting factors slightly.

Bioidentical estradiol:Chemically identical to human estradiol (preferred over conjugated equine estrogens like Premarin).

MUST combine with progesterone if uterus intact to prevent endometrial hyperplasia/cancer.

Timing:Starting HRT within 10 years of menopause (<60 years old) is associated with cardiovascular benefit. Later initiation may increase risk.

Symptoms of Abnormal Estradiol (E2)

Low Estradiol (E2)

Raise Low Estradiol in Men (if <20 pg/mL)

High Estradiol (E2)

Optimize Estradiol in Premenopausal Women

Causes of Abnormal Estradiol (E2)

Low Levels

Lifestyle Support for Healthy Estrogen Balance

High Levels

Maintain healthy body fat:Men <10% or women <18% body fat often have low estradiol due to insufficient aromatization/ovarian function. Conversely, obesity increases estradiol via excess aromatase.
Cruciferous vegetables:Broccoli, cauliflower, kale contain DIM and I3C, which support estrogen metabolism and clearance of harmful metabolites.
Fiber:25-35 g/day promotes estrogen excretion via bile. Low fiber=enterohepatic recirculation of estrogen.
Limit alcohol:Alcohol impairs estrogen clearance via liver, raising levels.
Phytoestrogens:Soy, flaxseed contain weak plant estrogens that may modulate estradiol activity (evidence is mixed).

When to Retest

Low libido, decreased sexual desire (both sexes)
Vaginal dryness, painful intercourse (women)
Hot flashes, night sweats (postmenopausal women)
Mood swings, depression, anxiety
Bone loss, osteoporosis, increased fracture risk
Fatigue, low energy
Cognitive decline, brain fog, memory problems
Joint pain, stiffness
Dry skin, thinning hair
Increased abdominal fat (postmenopausal women)
Erectile dysfunction (men with very low E2)

Scientific Evidence

Low estradiol in men <15 pg/mL harms bone density and libido. In postmenopausal women, low estradiol causes hot flashes and bone loss.

Gynecomastia (breast enlargement in men)|Water retention, bloating|Mood swings, irritability, emotional lability|Decreased libido, erectile dysfunction (men)|Acne, oily skin|Weight gain, especially hips/thighs (women)|Breast tenderness (women)|Increased risk of blood clots (VTE) if very high|Migraine headaches (women)|Heavy menstrual bleeding (premenopausal women)|Increased cancer risk (endometrial, breast) if chronically elevated without progesterone balance

Source:High estradiol in men >50 pg/mL often due to obesity or excessive TRT. In premenopausal women, persistently high estradiol may indicate estrogen dominance or ovarian cysts.

Menopause:Ovarian follicles depleted, estradiol production drops to <30 pg/mL. Most common cause of low estradiol in women >45.|Premature ovarian insufficiency (POI):Ovarian failure before age 40. Autoimmune, genetic (Turner syndrome), chemotherapy/radiation.|Hypothalamic amenorrhea:Excessive exercise, low body fat, chronic stress, eating disorders suppress GnRH→LH/FSH→estradiol axis.|Aromatase inhibitor overuse (men):Excessive AI use on TRT crashes estradiol.|Anorexia nervosa, extreme calorie restriction:Body shuts down reproductive axis to conserve energy.|PCOS with anovulation:Some PCOS women have low estradiol due to chronic anovulation (others have estrogen dominance).|Pituitary or hypothalamic disorders:Tumors, trauma, Sheehan syndrome suppress LH/FSH, lowering estradiol.

Obesity in men:Excess fat tissue contains aromatase enzyme, converting testosterone→estradiol.|Excessive testosterone replacement therapy (TRT) in men:More substrate for aromatization=higher estradiol.|Estrogen-secreting tumors:Rare ovarian or adrenal tumors (granulosa cell tumor).|Liver disease (cirrhosis):Impaired estrogen clearance leads to accumulation.|Hyperthyroidism:Increased SHBG and altered estrogen metabolism.|Exogenous estrogen use:HRT, oral contraceptives, or inadvertent exposure (phytoestrogens, xenoestrogens).|Aromatase excess syndrome (rare genetic condition).

Source:If starting or adjusting HRT (women):Retest estradiol after 3 months to ensure target range (40-100 pg/mL for symptom relief and bone protection).|If on TRT (men):Check estradiol along with total/free testosterone every 3-6 months. Adjust aromatase inhibitor dose if needed to keep E2 in 20-40 pg/mL range.|If postmenopausal and symptomatic:Baseline estradiol to assess if HRT candidate.|If premenopausal with irregular cycles:Test estradiol on day 3 of cycle (should be 30-100 pg/mL) and day 21 (should be 80-200 pg/mL with progesterone >5 ng/mL).|If optimizing bone density:Retest annually along with bone markers (CTX, P1NP) and DEXA scan every 1-2 years.

Estradiol and Bone Density

Estradiol is the dominant hormone regulating bone remodeling in both sexes. Men with estradiol <10 pg/mL have 3x higher fracture risk. Postmenopausal estradiol decline causes rapid bone loss (~2-3%/year for first 5 years). HRT reduces fracture risk by ~30%.

Source:Khosla S, et al. Estrogen and the skeleton. Trends Endocrinol Metab. 2012;23(11):576-581.

Menopause HRT and Cardiovascular Disease

The WHI (Women's Health Initiative) initially suggested HRT increased CVD risk, but reanalysis shows timing matters. Starting HRT within 10 years of menopause (<60 years) reduces CVD events by 30-50%. Starting HRT >10 years post-menopause or >60 years old may increase risk.

Source:Manson JE, et al. Menopausal hormone therapy and long-term all-cause and cause-specific mortality. JAMA. 2017;318(10):927-938.

Estradiol and Alzheimer's Risk

Observational studies suggest estradiol supports cognitive function and may reduce Alzheimer's risk. Estradiol enhances synaptic plasticity, neurogenesis, and cerebral blood flow. Early HRT initiation (within 5 years of menopause) associated with 30-50% lower dementia risk;late initiation shows no benefit or potential harm.

Source:Maki PM, Henderson VW. Hormone therapy, dementia, and cognition:the Women's Health Initiative 10 years on. Climacteric. 2012;15(3):256-262.

Provider	Includes	Annual Cost	Biomarkers
Superpower	✓	$199	100+ (150 with ratios)
WHOOP Advanced Labs	✓	$349	65
Labcorp OnDemand	—	$398	30+
Life Extension	✓	$486	40+
Everlywell	✓	$468	83
Mito Health	✓	$349	100+
InsideTracker	✓	$680	54
Function Health	✓	$365	100+
Marek Health Base	—	$250	65
Marek Health Comprehensive	✓	$495	70+
Marek Health Complete	✓	$895	100+
Marek Health Executive	✓	$1950	150+
Blueprint	—	$399	100+
Quest Health	—	$Varies	75+
Empirical Health	—	$190	100+
Oura Health Panels	—	$99	50
SiPhox Health	✓	$125	60
Hims Labs Base	—	$199	50
Hims Labs Advanced	✓	$499	120+
Healthspan	✓	$4188	80+
Vitality Blueprint Standard	✓	$375	85
Vitality Blueprint Elite	✓	$700	129