Too Much of a Good Thing: Estrogen and Breast Cancer
Holy smokes. This cancer prevention series, sparked by my longtime frustration with “crap for the cure,” has turned into a research monstrosity. If there’s one thing most everyone agrees on, it’s that cancer is a complex disease with multiple modalities and causes. This is what makes finding The Cure difficult to the point of impossible (let’s face it: all our medical advances over the past 70 years have increased the average life expectancy of cancer patients by mere weeks). While prevention is rather simpler, the study of decreasing risk still leads me in many directions.
We’ve already discussed many avenues of cancer prevention, including anti-angiogenic dietary choices, adequate sleep, low carbohydrate intake, stress reduction, and more. Now, it’s time to talk hormones.
Hormones are a critical part of the biochemical courier system by which our bodies’ myriad components communicate with each other to maintain homeostasis. As with most health factors, the effects of hormones can be thought of as lying on a U-shaped curve. Too little of a given hormone is detrimental, the right amount is beneficial, and too much becomes detrimental again.
Consider estrogen. Most women are aware that excessive levels of this important hormone are correlated with substantially higher risk of breast cancer. High estrogen levels (along with high cortisol, low iodine, low progesterone, and low vitamin D-3) are part of the classic breast cancer patient profile. Furthermore, over 65 percent of breast cancers are defined as estrogen-dependent (Epstein et al, The Breast Cancer Prevention Program).
Of course, correlation does not prove causation, but there is sufficient evidence of the estrogen-breast cancer link that women would do well to pay attention to their levels of the hormone. Happily, even if the estrogen theory ultimately proves incorrect, the action plan advised for reducing estrogen levels will benefit your health in other ways.
Here’s what most researchers currently believe: Estrogen itself doesn’t cause cancer, but the ability of carcinogens to produce tumors increases in its presence. In other words, “Estrogens can take a cell that is capable of becoming cancerous and increase the probability that it will do so” (Dr. Lindsey Berkson, Hormone Deception).
Unfortunately for women, our modern environment is an estrogenic soup. Dietary phytoestrogens; xenoestrogens in herbicides, industrial waste, cosmetics, and everyday plastics; even prescribed, synthetic estrogens that wind up in the food chain – all these pass through or build up in our systems, sending our lifetime exposure to estrogen skyrocketing well beyond normal levels.
Still, we can take action to reduce estrogen dominance in our bodies:
The most obvious step is to address the quantity of estrogen produced by our own bodies. We can accomplish this by reducing bodyfat. Particularly in postmenopausal women, bodyfat is the primary source of estrogen production; in fact, the Harvard Nurse’s Health Study found that overweight women had estrogen levels as much as 100% higher than those of lean women.
Once you understand that insulin promotes the storage of bodyfat, and that cancer cells thrive on sugar delivered courtesy of insulin, you will be unsurprised to learn that chronically high insulin levels, like excessive bodyfat, are associated with increased breast cancer risk. So, we are well advised to minimize insulin secretion, which will also lead to lower bodyfat levels. But how?
At peril of sounding like a broken record: Stop eating foods that spike your blood sugar, necessitating the release of insulin to normalize blood glucose levels. Specifically, don’t eat grain, legumes, or sugar in any form. Enjoy meats, vegetables, and healthful fats instead. You’ll find it easy to keep your total (not net) carbohydrate intake around 50-100 grams per day – and if you compare the nutrient density of your new diet to that of your old one, you’ll be amazed by the super-RDA results.
What other steps can you take to reduce your body’s estrogen production?
Participate in frequent, moderate exercise, which is demonstrated to reduce blood estrogen levels. “Moving slowly,” as Mark Sisson calls exercise at about 70% of your maximum heart rate (think brisk but comfortable walking), also sets up other hormones to send metabolism-speeding signals and increases insulin sensitivity.
Limit alcohol consumption. Sorry, ladies, but alcohol boosts circulating estrogen levels. According to the New England Journal of Medicine, partaking of 2-3 drinks per day (as opposed to none) increases the breast cancer risk of postmenopausal women by 15%. (The good news is that one drink per day scarcely increases risk at all, and may provide other benefits ranging from cardiac protection to stress reduction.)
The alcohol effect is amplified in overweight women, premenopausal women, and women taking hormone replacement therapy, because their base estrogen levels are higher. In fact, E.S. Ginsburg found in a double-blind, crossover study that estradiol (natural estrogen) levels increased by 327% following alcohol consumption by women on HRT. Not good.
Next, we need to look at any estrogens and estrogen-mimicking substances we are intentionally putting into our bodies. Hormonal contraception, anyone?
Yes, I know. My ObGyn – like yours, no doubt – said the Pill now contains “safe, minimal levels” of estrogen and/or progestin. Oh yeah? My thermogram revealed excessive vascularity indicative of a highly estrogenic state — and increased cancer risk.
Even the package inserts admit that use of oral contraceptives increases risk. This is particularly true when these pharmaceuticals are used by young women and/or for prolonged periods. Early use of oral contraceptives, like postmenopausal use of HRT, increases a women’s lifetime exposure to estrogen. The Pill also induces many women to retain excessive bodyfat.
This is tough, I know. It’s hard to find an option that can compare to the ease, affordability, and effectiveness of hormonal contraceptives. (My reading on the subject leads me to favor the non-hormonal, copper IUD.) It’s easy to shrug off the warnings…again and again…but I beg you to reconsider.
If your own health isn’t enough of a motivator, consider the environment, which affects everyone else’s health, too: synthetic estrogens are showing up in measurable levels in wildlife that is part of our food chain. How do these substances get from pharmacy to fish? Through your urine. Be responsible.
Take care with hormone replacement therapy, too. Breast tissue is, by nature, particularly sensitive to hormonal influence — especially the balance of estrogen and progesterone. HRT is too big a topic to tackle here, but suffice it to say that if you’re going to mess with it, you’d better be darn sure your provider knows how to properly balance your hormonal levels.
Okay, so you’ve reined in your own estrogen production as much as possible, and you’ve ceased the blatant addition of unnatural hormones to your system. Unfortunately, there’s a whole other set of estrogen-related factors we need to consider: environmental toxins. We’ll cover those in this series’ next post.
Previous posts in this series: Cancer for a Fortnight, Before Early Detection, In the Beginning: The Cancer-Inflammation Connection, Only YOU Can Prevent Inflammation, Supply Lines: The Importance of Angiogenesis, Short-Circuit: Inhibiting Angiogenesis Naturally, Please Don’t Feed the Cancer, Blaming the Victim?, Fighting Mad(ness), Crap for the Cure.