Too much estrogen can cause heavy periods, breast pain, fibroids, and premenstrual irritability. It can also suppress thyroid function and increase the risk of breast cancer.
To understand what works to lower estrogen, you need to think about the types of estrogen and why they’re high.
The many types of estrogen
Estrogen is not one thing. Instead, estrogen is a generic term that can refer to any of the following:
- Estradiol, which is the main (and best) estrogen from our ovaries.
- Estrone from body fat.
- Estrogen metabolites from intestinal bacteria.
- Xenoestrogens or endocrine-disrupting chemicals (EDCs), which are environmental toxins that act like estrogen.
👉 Tip: The estrogen in birth control (ethinylestradiol) is a xenoestrogen.
- Finally, there are plant estrogens (phytoestrogens), which are so weak that they generally have a beneficial anti-estrogen effect. Read Phytoestrogens are not estrogen.
Causes of too much estrogen
1) Hormonal birth control
The estrogen ethinylestradiol is stronger than the body’s own natural estradiol and so can damage gut bacteria and impair estrogen metabolism or detoxification.
2) Impaired estrogen metabolism or detoxification
All estrogens (including xenoestrogens) must be detoxified in a two-step process through the liver and bowel.
Step 1 happens in the liver and requires B vitamins, selenium, and the amino acid glycine. This step of estrogen metabolism can be impaired by xenoestrogens and alcohol, which is why alcohol causes higher blood levels of estrogen and increases the risk of breast cancer.
Step 2 happens in the bowel, where conjugated estrogens are escorted out of the body. In the presence of healthy gut bacteria, conjugated estrogens leave the body. In the presence of unhealthy bacteria, conjugated estrogens are de-conjugated and reactivated by the enzyme beta-glucuronidase. Reactivated estrogens can then be reabsorbed in a process called enterohepatic recirculation or “gut-liver recirculation.” The result is estrogen excess.
Estrogen can increase during the years before menopause. It can also become erratic, swinging from low to high and back to low again. I call this the perimenopausal estrogen roller coaster, and it includes the hot flushes and insomnia of estrogen deficiency, plus the breast pain and irritable mood of estrogen excess.
👉 Tip: At its highest point, your estradiol blood level should not exceed 270 pg/mL (1000 pmol/L).
4) Insulin resistance
Insulin resistance promotes an estrogen called estrone which can be a problem with polycystic ovary syndrome (PCOS) and after menopause. Too much estrone can increase the risk of uterine cancer.
5) Histamine and mast cell activation
Estrogen stimulates mast cells to make more histamine plus estrogen down-regulates the DAO enzyme that you need to clear histamine. The result is more histamine, which, unfortunately, then stimulates the ovaries to make more estrogen. The net result is a vicious cycle of:
estrogen → histamine → estrogen → histamine.
For many women, symptoms of “estrogen dominance” such as PMS, period pain, and heavy periods improve by reducing histamine by avoiding cow’s dairy and other strategies. Read The curious link between histamine intolerance and estrogen.
6) Estrogen receptor hypersensitivity
Your actual amount of estrogen is only part of the story. It also matters how sensitive you are to it.
For example, you’ll be more sensitive to estrogen (and not in a good way) if you have chronic inflammation or high histamine or if you’re deficient in iodine. Read Why I prescribe iodine for PMS, breast pain, and ovarian cysts.
You’ll be less sensitive to estrogen if you consume beneficial phytoestrogens from legumes, nuts, and vegetables.
👉 Teenagers are more sensitive to estrogen so can experience heavy periods.
What is estrogen dominance?
Estrogen dominance usually means too much estrogen, but it can also describe a situation of normal estrogen and too little progesterone.
I don’t like the term “estrogen dominance” because I prefer the more precise terms estrogen excess and progesterone deficiency. It’s possible to suffer both simultaneously. Read Why I don’t use the term estrogen dominance.
👉 Endometriosis is affected by estrogen, but it’s not caused by estrogen. Instead, it’s a disease of immune dysfunction.
How to lower estrogen
- Don’t take hormonal birth control.
- Reduce alcohol to promote healthy estrogen metabolism.
- Eat vegetables for their beneficial phytoestrogen content. Phytoestrogens promote healthy estrogen metabolism and shelter the body from too much estrogen.
- Maintain a healthy body weight to reduce the production of estrone.
- Reduce exposure to xenoestrogens such as plastics and pesticides.
- Avoid inflammatory foods such as dairy to reduce histamine and hypersensitivity to estrogen.
- Avoid cow’s dairy to reduce histamine.
Best supplements to lower estrogen
- Calcium d-glucarate promotes healthy estrogen metabolism by inhibiting the bacterial enzyme beta-glucuronidase thereby reducing enterohepatic recirculation or the “gut-liver recirculation” of estrogen.
- Iodine down-regulates estrogen receptors, thereby decreasing estrogen sensitivity. Iodine is particularly helpful for breast symptoms such as tenderness or breast cysts. Iodine is safe up to a dose of 500 mcg (0.5 mg), but higher dose iodine can harm the thyroid.
- Natural progesterone counterbalances estrogen and therefore can lighten periods and improve breast tenderness and premenstrual irritability. The progestins of hormonal birth control are not progesterone. Read The crucial difference between progestins and progesterone.