BPA IN CANS & PLASTIC BOTTLES INCREASES BLOOD PRESSURE

A new study has found that ingestion of beverages kept in cans lined with bisphenol A, BPA, raises blood pressure.  BPA is widely found in plastic bottles, plastic packaging, receipt paper, and the linings of food and beverage cans. Previous studies have linked chronic BPA exposure with increased rates of heart disease, diabetes, thyroid dysfunction, and cancer.  This new study reveals that BPA exposure is not only a problem over the long-term, but that blood pressure increases within hours of ingesting products kept in BPA-lined cans. 

The researchers found that when study participants drank soy milk from glass bottles their urinary BPA levels remained low. But, within two hours of drinking soy milk from a can, their levels of BPA were 16 times greater.  As their BPA levels rose so did their blood pressure with systolic readings increasing by an average of 5 mm Hg.  To put this rise in perspective, every 20 millimeter increase in systolic blood pressure doubles cardiovascular disease risk. The researchers chose soy milk as the beverage in the study because it does not have any properties that are known to increase blood pressure, and, unlike soda, fruit juice,  tomato juice and other acidic products which are known to promote BPA leaching, soy  milk is neutral.

While a single instance of increased blood pressure is unlikely to be harmful, the findings suggest that for people who drink from multiple cans or plastic bottles every day, the repeated exposure over time could contribute to hypertension.  BPA is an endocrine disrupter that can mimic the actions of estrogen.  BPA is known to block certain estrogen receptors that are thought to be responsible for repairing blood vessels and controlling blood pressure. The chemical may also affect blood pressure indirectly by disrupting thyroid hormone.

What to do:  Because of growing concerns about BPA, some packaged products now carry “BPA free” claims on their labels. However, these products often contain chemically similar alternatives – like bisphenol S that also leach chemicals with estrogenic activity.  To minimize exposure avoid #3, #6, #7 plastics and aluminum cans as much as possible.  Products that are liquid and/or acidic cause more chemical leaching.  Look for products packaged in glass bottles instead.  Avoid freezing, microwaving, or machine dishwashing plastics as these processes degrade the plastic allowing more BPA to leach into your foods.  Store foods in glass or stainless steel containers. 

Adapted from articles available at:

http://newsroom.heart.org/news/cans-lined-with-bisphenol-a-may-increase-blood-pressure?preview=0aef

http://well.blogs.nytimes.com/2014/12/08/bpa-in-cans-and-plastic-bottles-linked-to-quick-rise-in-blood-pressure/?ref=health&_r=0

Source:

Bae S, Hong Y-C. Exposure to Bisphenol A from drinking canned beverage increases blood pressure: Randomized crossover trial. Hypertension.  2014; DOI: 10.1161/HYPERTENSIONAHA.114.04261