Diabetes and Obesity are Related to Plastics in Food and Beverage Containers
by Elmer M. Cranton, M.D.
Copyright © 2008 Elmer M. Cranton, M.D.
Tiny residues of toxic synthetic chemicals are released from plastic food and beverage containers, baby bottles, dental sealants, and many other products. These plastic-derived chemicals increase the risk of diabetes and obesity. In a recent report co-authored by Dr. Angel Nadal, it was stated that widespread use of plastics in beverage and food containers might (at least partially) explain the epidemic of diabetes and obesity now occurring in industrialized countries. Diabetes increases the incidence of obesity, atherosclerosis, coronary heart disease, infectious disease, eye disease and kidney disease.
Repeated exposure to BPA causes insulin resistance at the cell level, which leads to type II diabetes. Tissues lose their sensitivity to insulin, causing the pancreas to produce even more insulin, further increasing insulin resistance and diabetes. This leads to a progressive cycle that reinforces itself.
Bisphenol-A (BPA) leaches out of plastic storage containers to contaminate foods, beverages and drinking water. BPA is also used to line "tin" cans, milk cartons, and other metal and paper-board containers commonly used to package foods and beverages. Alarmingly, BPA content is greatest in clear, polycarbonate plastics, which were previously thought to be safer and had the highest hardness number embossed within a triangle on the bottom. Bisphenol-A is used to make plastic hard and is found almost everywhere in modern life. More than 6 billion pounds were put into products in 2004 alone.
So how do we find and safely store food and beverages? Most bottled water is sold in plastic containers. One way is to purify water by distillation. An easier method is to install an under-counter reverse osmosis water purifier, with an activated charcoal pre-filter. Activated charcoal will remove BPA. Use glass or stainless steel containers for storage. There are ways to avoid potentially harmful plastics.
Plastic containers labeled as safe to microwave contain more even BPA. And it seems likely that additional BPA is released while microwaving.
In another report, co-authored by Dr. Ana M. Soto, at Tufts University Medical School in Boston, it is stated that animal studies show exposure to BPA early in life can lead to obesity.(2) Very low doses (doses considered safe by the EPA) can cause diabetes-related insulin resistance in mice.
Blood testing by the U.S. Public Health Service (CDC) shows that BPA exists widely throughout the human population. It contaminates our water supplies, effecting animals as well as humans. BPA act as a synthetic female estrogen-like hormone, which might contribute to breast cancer in women.
A report in the Journal Environmental Health Perspectives reviews data from 115 published studies on BPA. It reports that 94 published animal studies show harmful effects.(3) Is it a coincidence that all 11 studies funded by the plastics industry conclude that BPA safe and nothing to worry about, while 90 percent of the 104 government or university-funded studies report evidence for harm?
Frederick vom Saal, a developmental biologist at the University of Missouri who reported these findings, is concerned about the impact of the low levels of BPA now measured widely in humans. In mice and rats there is evidence that those same levels cause structural damage to the brain, hyperactivity, abnormal sexual behavior, increased fat formation, insulin resistance (a precursor to diabetes), early puberty and disrupted reproductive cycles .(3)
California's legislature has introduced a bill banning BPA in children's products; if successful, it would be the first ban on the chemical in the world. (Los Angeles Times, Marla Cone, 13 Apr 2005; USA Today, Elizabeth Weise, 14 Apr 2005).
Other harmful chemicals in plastics
Food and beverage containers are be made from various types of plastic and plasticizers: Phthalates, polycarbonate, polyethylene terephthalate, polypropylene, polyethylenetherephtalate, ethylene vinyl acetate, high-density polyethylene, low-density polyethylene , polyvinyl chloride or vinly), polystyrene, polybutylene, Nalgene, dilaurylthiodipropionate, 3(3,5-di-tert-4-hydroxyphenyl) propionate, and many others. All release small amounts of chemicals and plasticizers into foods and beverages. BPA is just one example.
Phthalates act to disrupt hormone pathways in the body. Phthalates and other chemical substances in plastics commonly contaminate food and beverages. Phthalates make brittle plastic softer, pliable, and more suitable for uses like toys and medical equipment. Phthalates are harmful to normal childhood development, especially sexual development. These chemicals leach out of plastics into the environment and can cause developmental defects in children, among other things. Phthalates also enter the body from intravenous bags used to infuse fluids and blood in the hospitals and clinics.
Toxicity studies cited by the plastics industry ignore the additive effect of synergy. In combination with other commonly used products, toxicity of chemicals from plastics can be greatly potentiated by synergistic effects. This occurs when two or more chemicals combine to elevate the combination’s toxicity to many times greater than that of the individual chemicals. Synergy is an important issue that is mostly disregarded by the FDA. Low dose synergy is real. Besides plastics, other household chemicals can synergize the toxicity of plastics. More chemicals can be found under the average kitchen sink today than were present in a fully stocked chemistry laboratory 60 years ago.
Although the evidence thus far stems mainly from animal studies, the action of insulin and other hormones in all mammals is the same as it is in humans.
1. Alonso-Magdalena P, Morimoto S, Ripoll C, Fuentes E, Nadal A. The estrogenic effect of Bisphenol-A disrupts pancreatic beta-cell function in vivo and induces insulin resistance. Environ Health Perspect. 2006 Jan;114(1):106-12.
2. Harder B. Diabetes from Plastic? Science News. Jan 21, 2006;169:36-37.
3. vom Saal FS, Hughes C. An extensive new literature concerning low-dose effects of bisphenol A shows the need for a new risk assessment. Environ Health Perspect. 2005 Aug;113(8):926-33
Copyright © 2011 Elmer M. Cranton, M.D., all rights reserved