Two of the most important hormones are undoubtedly estrogen and progesterone. They work together with a complex synergy. These “sex hormones” can work sometimes in concert and other times in opposition. Estrogen tends to favor growth and expansion while progesterone promotes stabilization and contraction.Yin and yang.

During a normal menstrual cycle, estrogen dominates the initial follicular phase when the female is preparing for ovulation. During this part of the cycle, there is build up of the endometrial lining within the uterus. There is then a transition after ovulation to the luteal phase where progesterone plays a more dominant role. Progesterone stabilizes the endometrial lining that will ultimately slough off in menstruation before the cycle begins again.

There are a variety of health issues and conditions you can see relative to the interplay of estrogen and progesterone, but for the purposes of this blog, we will focus on what is almost certainly the most important one: estrogen dominance.

Estrogen dominance, also sometimes referred to as unopposed estrogen, is a crucial issue in women’s health today. We will cover some of the most common underlying causes of this imbalance and their implications.

The four most common causes of estrogen dominance by my understanding are obesity, xenoestrogens, copper toxicity and stress. The more adipose tissue a person has on their frame, the higher the amount of circulating estrogen so that alone can be the central problem.

It is still assumed by many that the sequence of events for weight gain is: too many calories and not enough exercise leads to weight gain that can then cause insulin resistance with a higher risk of diabetes and other health problems. This is not a blog about weight management, but that scheme is generally incorrect. The reasons for weight gain go far beyond simple formulas of calories in and calories expended. Research is also starting to show it is likely more common that people develop insulin resistance and then secondary obesity.

Xenoestrogens are estrogen-like compounds we are exposed to from our environment. Common sources include our food supply relative to hormones used in the production of beef, chicken, and dairy. We also ingest pesticides and herbicides used on other types of food plus plastics and other chemicals. We all have a toxic load in our bodies and the toxins that exacerbate estrogen dominance are among the most important.

Copper toxicity and copper/zinc imbalance is a complex topic, but relatively common and not generally addressed in medical circles. I’ve had to grind through many different sources to understand the implications of unbound copper on the body. A place to start is to do some research on the subject (see below) and have serum copper and plasma zinc levels checked. A rough goal for copper is 100 or below and rough goal for zinc is 100 or above. You need zinc/copper in at least a 1:1 ratio to offset the copper toxicity. There are many other aspects of the problem–especially in terms of mental health–that are beyond the scope of this blog.

Stress affects the body in many ways. Cortisol is often called “the stress hormone.” When the body shunts cholesterol through the “mother hormone” pregnenolone down the cortisol pathway, the body can have a relative deficiency of progesterone. Progesterone is needed to balance estrogen, so this also can be a factor when it comes to unopposed estrogen.

So what are the conditions, signs, and symptoms of estrogen dominance? Fibroids in the uterus, endometriosis, migraine headaches, breast cysts, breast lumps, breast swelling, breast tenderness, PMS, heavy menstrual bleeding, intense menstrual cramping, and others. Unopposed estrogen is a major factor in breast cancer risk. Too much estrogen can cause dense breast tissue that makes a mammogram more difficult to interpret.

If you have some of these signs, it’s worth doing more research and there are many good resources (see below) on the Internet. The Hormone Cure by Sara Gottfried, MD is an excellent book on hormone management. You may need to be your own advocate to improve your health and stay safe relative to your estrogen/progesterone balance.

Andrew Lenhardt, MD


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