We aren't sure how Bisphenol A (BPA) (found in plastic food containers) affects human beings — especially developing fetuses and young children — and if concerning test results in animal subjects translate to people. Should BPA be banned from baby bottles, as it has been in other countries like Canada?   Unfortunately, our ability to detect chemicals in our bodies is running ahead of our ability to understand exactly how them may affect us.

An estimated 93% of Americans have detectable levels of BPA in their bodies according to the Centers for Disease Control and Prevention. However,  once we stop being exposed to the chemical, BPA levels can drop dramatically. We can rid ourselves of BPA fairly quickly, unlike other more long-lasting chemicals like lead.

That's the conclusion of a new study published in the journal Environmental Health Perspectives. A team of researchers from the Silent Spring Institute, the Breast Cancer Fund and Vassar College took five families from the San Francisco Bay area and had them stop using canned foods and plastic food packaging for several days. The scientists found that BPA levels among the family members dropped by an average of over 60% — but once they went back to their normal diet, the BPA levels went back up as well. That's pretty strong evidence that restricting use of certain plastics and packaging can significantly reduce exposure to the chemical, and whatever harm it may do.

Here's how the study worked: the five families of four provided urine samples for two days while they ate their normal diets. That gave researchers a background level for BPA and some phthalates — plasticizing chemicals that have also been tagged as endocrine disruptors (

naturally occurring compounds or man-made substances that mimic or interfere with the function of hormones in the body). Next, the researchers gave each family three days' worth of freshly prepared organic meals and snacks, stored in glass and stainless steel containers. (One popular source of BPA is in the liner inside canned food.) The families gave  samples on the second and third days that were tested for BPA and phthalates. Lastly, the families returned to their normal diets for three days, and were tested twice again.

In addition to BPA, the researchers also tested for the phthalate DEHP — which is also found in food packaging — as well as DEP and several other chemicals that are not used often in packaging. That mix of chemicals was chosen to give the research team a better idea of the role that plastics and packaging might play in exposure to BPA. The fact that BPA levels among the families dropped when their diet changed — but levels of DEP, which is used in fragrances, didn't — underscores the importance of food packaging in exposing people to BPA.

Is this study significant?  Although this research was peer-reviewed, it was a small study and one that was carried out by environmental groups that have raised concerns about BPA and other potentially toxic chemicals in the past. But if you are worried enough about BPA and phthalates to want to cut down your exposure, avoid canned foods and use glass or stainless storage containers.  There are also more plastic  products available that are BPA-free, including baby bottles.

Industry has registered its skepticism of this study and the the American Chemistry Council has stated:
This study simply confirms these reassuring points: that consumers have minute exposures to BPA and DEHP from food sources, and that the substances do not stay in the body, but are quickly eliminated through natural means. Additionally, data from U.S. Centers for Disease Control and Prevention and Health Canada have shown that typical consumer exposure to BPA and DEHP, from all sources, is up to 1,000 times lower than government-established safe exposure levels. “Consumers should feel confident that they can continue to eat healthy canned or packaged foods because materials intended for use in food contact are approved by the U.S. Food and Drug Administration."

EDITOR'S NOTE:   This is an interesting article because it demonstrates how one study can be interpreted in several ways and why it is important to have large randomized controlled studies to get solid answers.     The "experiment" above sounds like it was well designed but the numbers are extremely small so questions about bias, misinterpretation and control are very possible.   The comment from the American Chemistry Council points out a common problem with epidemiology studies:  when does small exposure turn into unsafe levels of exposure?  This is one of the main reasons we cannot always prove cause and effect when we talk about environmental exposure.  Because this latter organization represents the chemical industry, they too can be biased.  The National Institute of Environmental Health Sciences and the National Toxicology Program are finding new ways to study the impact of chemicals, especially related to their effect on our hormones, which should help get some solid answers.     BTW,  I've stopped microwaving in plastic.

Scientists have discovered four new genes associated with an increased risk of late-onset Alzheimer’s disease. The findings will help researchers explore new therapies and allow doctors to better predict who will develop the disease.

The Alzheimer’s Disease Genetics Consortium conducted the research in collaboration with 44 different universities and research centers, including Northwestern University. The study, published in the current issue of Nature Genetics, is the largest of its kind.

The results of the study double the number of genes currently known to contribute to Alzheimer’s. Of the four genes previously confirmed, the gene for apolopoprotein E-e4, called APOE-e4, has the largest effect on risk. The genes discovered in this study are called MS4A, CD2AP, CD33 and EPHA1.

Alzheimer’s disease affects more than 13 percent of people age 65 and older and nearly half of those 85 and older. Women are more likely than men to have this common form of dementia, possibly because women have a higher life expectancy.

Although there are currently no effective treatments or preventative measures for Alzheimer’s, the ability to predict who will develop the disease will be important when preventative steps become available. The findings will also help researchers identify the disease’s earliest stages and understand the events leading to brain damage. Alzheimer’s is associated with the destruction of large parts of the brain and is characterized by the loss of cognitive abilities, including memory loss and intellectual decline.

The White House and Congress have reached a budget deal over last weekend to keep the federal government running for the short term. Congress is expected to vote on the longer-term budget soon.  Women's health and reproductive health was taken off the table for the short term solution, however, these issues are likely to rise when Congress begins debating long term budget solutions.  Here's the issue:

Conservatives (mainly Republicans)  have been pushing to strip federal funding from Planned Parenthood during the budget talks.  In addition, they want to redirect federal dollars now set aside for family planning and women's health services into block grants to be managed by the states. Democrats argue this policy change would give governors and state legislatures more ability to cut funding for services opposed by conservatives.  For those of you who may not understand the political implications of federal vs state funding policies, consider this.   If one state is socially liberal and is next to a more conservative state, there is a real possibility that more poverty stricken individuals will consider moving to a state with more liberal assistance programs, thus increasing the burden on the state that is more "giving".   This creates a two tiered system of entitlement and in the end creates further divisiveness.

I looked up the services provided by Planned Parenthood in my home state of Illinois.   In 2009, 70,738 people received STD testing (includes both women and men), 24,055 women had PAP tests, 26,579 had breast exams, and 54,470 were seen for birth control.  More than 95% of those served earned less than $21,000 per year.   Who do you think would be hurt most if Planned Parenthood lost their funding?

High-fiber diets during early adult years may lower lifetime cardiovascular disease risk

A new study from Northwestern Medicine shows a high-fiber diet could be a critical heart-healthy lifestyle change young and middle-aged adults can make. The study found adults between 20 and 59 years old with the highest fiber intake had a significantly lower estimated lifetime risk for cardiovascular disease compared to those with the lowest fiber intake.  This is the first known study to show the influence of fiber consumption on the lifetime risk for cardiovascular disease.

“It’s long been known that high-fiber diets can help people lose weight, lower cholesterol and improve hypertension,” said Donald M. Lloyd-Jones, M.D., corresponding author of the study and chair of the department of preventive medicine at Northwestern University Feinberg School of Medicine. “The results of this study make a lot of sense because weight, cholesterol and hypertension are major determinants of your long-term risk for cardiovascular disease.”

A high-fiber diet falls into the American Heart Association’s recommendation of 25 grams of dietary fiber or more a day.  Lloyd-Jones said you should strive to get this daily fiber intake from whole foods, not processed fiber bars, supplements and drinks.

“A processed food may be high in fiber, but it also tends to be pretty high in sodium and likely higher in calories than an apple, for example, which provides the same amount of fiber,” Lloyd-Jones said.

For the study, Hongyan Ning, M.D., lead author and a statistical analyst in the department of preventive medicine at Feinberg, examined data from the National Health and Nutrition Examination Survey, a nationally representative sample of about 11,000 adults.  Ning considered diet, blood pressure, total cholesterol, smoking status and history of diabetes in survey participants and then used a formula to predict lifetime risk for cardiovascular disease.

“The results are pretty amazing,” Ning said. “Younger (20 to 39 years) and middle-aged (40 to 59 years) adults with the highest fiber intake, compared to those with the lowest fiber intake, showed a statistically significant lower lifetime risk for cardiovascular disease.”  In adults 60 to 79 years, dietary fiber intake was not significantly associated with a reduction in lifetime risk of cardiovascular disease. It’s possible that the beneficial effect of dietary fiber may require a long period of time to achieve, and older adults may have already developed significant risk for heart disease before starting a high-fiber diet, Ning said.

As for young and middle-aged adults, now is the time to start making fiber a big part of your daily diet, Ning said.

Erin White is the broadcast editor. Contact her at ewhite@northwestern.edu