Healthy 19-50 year olds should consume no more than 2,300 milligrams of salt a day, about one teaspoon. More >
BPA Lowers Women's Fertility in Study
Another study has come out suggesting that BPA is not the harmless plastic additive it was once thought to be. But the bad news is different this time.
A small-scale study from the University of California, San Francisco found that BPA lowers the biological fitness of a woman's eggs. The study found that as the level of BPA in a woman's blood rose, the percentage of her eggs that fertilized normally when removed for in vitro fertilization dropped. A doubling of blood BPA led to a 50% decrease in the number of eggs that fertilized normally.
BPA (bisphenol A) is mainly found in polycarbonate plastic and the inner lining of some food cans. While many studies suggest that BPA can mimic estrogen and act as an endocrine disruptor, most of these studies have looked at animals, not humans. Endocrine disruptors are chemicals that either mimic or block hormones and can interfere with the body's normal functions in many different ways.
Over five billion pounds of BPA are manufactured yearly. Because BPA is so widespread, there has been increasing concern over the number of reports that suggest it may be harmful to humans. Before February 2010, the FDA's position on BPA was that it posed no risk to humans. That month, the FDA's position became that BPA exposure was "of some concern" for infants and children.
This study suggests that it may also be of concern to any woman who is still in her childbearing years.
The study looked at 26 women who were undergoing in vitro fertilization at the UCSF Center for Reproductive Health in 2007 and 2008. The BPA concentration in the women's blood was measured and compared with the ability of their eggs to undergo fertilization outside of the body.
The researchers point out that there is currently no routine clinical test available to measure the amount of BPA in a woman's blood or fat. They suggest that concerned women considering IVF treatment might want to reduce their exposure to BPA by modifications in lifestyle and diet.
Of course, concerned women who are considering the traditional method of fertilization might also choose to follow this advice.
The UCSF Program on Reproductive Health and the Environment has made a pamphlet available for anyone who is concerned about their everyday exposure to common substances that can harm their reproductive health. While not specifically about BPA, the pamphlet offers many recommendations on how individuals and society as a whole can lower exposure to chemicals known or thought to be toxic.
A corrected proof of an article detailing the study was published online by the journal Fertility and Sterility on December 3, 2010
December 29, 2010
No comments have been made