As you likely are aware, estrogens are a class of female (and male) sex hormones that are responsible for female sexual development, fertility, pregnancy and lactation. While estrogen has many beneficial effects, such as supporting proper bone strength, exposure to too much estrogen can cause problems, such as disrupted sexual development in both males and females, immune system abnormalities, birth defects, cancer and more.
There is substantial research on the role that phytoestrogens, such as those that come from soy or red clover, may have on health. Both positive and negative research exists in this area. However, phytoestrogens have been part of the human environment for thousands of years. Today, people have another class of estrogens to cope with in addition to exogenous and naturally-occuring; synthetic or environmental estrogens.
The phrase "environmental estrogens" describes a class of synthetic chemicals that have estrogen-like activity in the body. This is the most well-studied group of endocrine disrupting compounds. Exposure to environmental estrogens occurs through air, water, household products, food -- even breastmilk and in utero! The health risks associated with these constant, low-level exposures are not clear, but it is suspected that they are problematic.
Our exposure to environmental estrogens comes from many categories of chemicals, including plastics (containing phthalates, bisphenol A and others), pesticides and herbicides (such as dieldrin or atrazine), pharmaceuticals (e.g. DES, birth control pills), industrial chemicals like PCBs and more. Environmental estrogens are so toxic to our metabolic and endocrine systems that the Environmental Working Group has joined with the Keep a Breast organization to publish their own "dirty dozen endocrine disruptors" list.
These chemicals affect fertility, both directly in adults as well as by affecting sexual development in utero, in childhood and in puberty. They also can influence breast changes and increase rates of breast cancer in many instances.
With the ubiquitous nature of these chemicals, it's important for all patients to identify what their exposure level may be. The more you learn about these exposures, the easier it is to understand the importance of eating organic, filtering your water and choosing "clean" options whenever available, such as food packaged in glass over plastic.
Want to Know More?
- University of California Davis, Dept of Environmental Toxicity. http://www.envtox.ucdavis.edu/cehs/toxins/estrogens.htm
- Environmental working group Dirty Dozen list of endocrine disruptors. http://www.ewg.org/research/dirty-dozen-list-endocrine-disruptors