In the past, studies have shown a very slight increased risk for breast cancer with the use of hormonal birth control, or none at all. Now, a study published in the August 2014 issue of Cancer Research states that women taking birth control pills are at higher risk for breast cancer, and that the risk depends on the amount of estrogen in that particular pill. In fact, even birth control pills with current-day dosing of estrogens can significantly increase breast cancer risk. So what’s a girl to do?

How much estrogen is considered a high dose in birth control pills?

There are so many current formulations of birth control pills, don't use the same synthetic estrogen. So how does someone assess her particular risk for breast cancer? The package insert will always list the actual ingredients and the amounts of each. Most of these appear to be in a foreign and scientific language that only a pharmacist can decipher, but here is a little breakdown of what to look for.

What is considered a high dose of synthetic estrogen?

High: Birth control pills that had at least 50 micrograms of ethinyl estradiol or 80 micrograms of mestranol had a threefold higher risk of breast cancer. Some examples of these are Microgynon 50, Norinyl 1+50, Ogestrel 0.5/50, and Zovia 1/50 to name a few.

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Moderate: Those pills with 30 to 35 micrograms of ethinyl estradiol or 50 micrograms mestranol were associated with a 1.6-fold higher risk of breast cancer. Most of the birth control pills used fall into this dosing category. Commonly known ones are Ortho-Cyclen, Ortho-Novum, Balziva, and Nortrel.

Low: Those birth control pills with 20 micrograms of ethinyl estradiol were considered low-dose and did not seem to have a higher risk for breast cancer. These include names like Alesse, Beyaz, Lessina, Loryna, and Mircette.

You can view a spreadsheet of birth control pills with their dosages here.

What else besides estrogen will increase my risk of breast cancer?

It may not be the synthetic estrogen in birth control that is increasing the risk for some. Synthetic progestins (often mislabeled as progesterone to add to the confusion) are known to increase the risk for breast cancer as well. Pills using a triphasic combination that have at least 0.75 milligrams of the progestin norethindrone had more than a threefold higher risk of breast cancer.

Ones to look out for are Enpresse, Necon 7/7/7, Nortrel 7/7/7, and Ortho-Novum 7/7/7. The study in Cancer Research also found that the progestin ethynodiol diacetate increased the risk of breast cancer by 2.6 fold, which can be found in Demulen, Zovia, and the progestin-only preparation, Femulen.

Progestins do not act the same way in the body as does progesterone, so they actually increase cancer risk and blood clot risks, whereas natural progesterone decreases these risks. Although women with a family history of breast cancer should always be more cautious in their lifestyle choices, it is evident that all women are at an increased risk when exposed to these synthetic hormones.

How do estrogens in the environment add to breast cancer risk?

There are so many substances in our environment that act as xenoestrogens, which means foreign estrogens. A xenoestrogens will be recognized by the body as an estrogen, and it will attach to the same receptors as estrogen, like a key fitting one type of lock. The problem with xenoestrogens is that they often have much more powerful effects than natural estrogen, and the body cannot get rid of them very easily.

Commonly found in plastics, pesticides, fragrances, and cleaners, we are constantly being exposed to xenoestrogens that add up in our bodies. If you think about it, birth control pills are just one way we are exposed to synthetic estrogens at a pretty significant dose. But if you add all of the other chemicals that act on the estrogen receptors, the health risk is considerably higher.

Perhaps the most confusing aspect of this issue is that many chemical companies will tell you that the amount of chemicals that act as xenoestrogens in their products are very tiny (100-300 ppm); unfortunately, you really only need a fraction of that to have an effect on the cells of the body. These manufacturers don’t factor in exposure to multiple sources, which brings the total amount absorbed by the body, including through the skin and through the lungs, much higher.

How can you lower your exposure to estrogens and lower your risk for breast cancer?

The list of ways to decrease your exposure to estrogens and xenoestrogens is too large to include here, but the Environmental Working Group has a great starting reference guide. After you dive into that list, there are very significant changes you can make to lower your risk, starting today.

Perhaps the most significant change you can make is to eliminate dairy products from your and your children’s diet. This is because almost all of our dairy is derived from cows that are milked even while they are pregnant. The estrogen from pregnancy (estriol) is actually more potent than the more common estrogen, estradiol. Since hormones can dissolve in fat, they are secreted into the milk and then can pass into your diet as milk, cream, yogurt, cheese, and butter.

In addition, some cows are given extra hormones to produce even more milk, which are transferred to the milk. Cows that eat grain instead of grass will also be eating pesticide residue on their grain, which not only has a xenoestrogenic effect, but is stored in their fat tissue and milk.

Some other very important actions to take are reducing the amount of scented candles, air fresheners, and fragrances in cleaners, never heating up foods in plastic containers or placing hot foods in them, not using weed killers or insecticides in or around your home, avoiding dark hair dye, and having a very serious conversation with your doctor about any hormonal type of birth control.

Since these estrogens and xenoestrogens have an additive effect in your body, any amount of decrease in exposure makes a difference. You can take charge of your own risk by making healthier choices for yourself and your family.

Photo Credit: Getty Images


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