Not me.
Posted on 01/23/2006 3:03:47 PM PST by blam
Diabetes from a Plastic? Estrogen mimic provokes insulin resistance
Ben Harder
Exposure to small amounts of an ingredient in polycarbonate plastic may increase a person's risk of diabetes, according to a new study in mice.
The synthetic chemical called bisphenol-A is used to make dental sealants, sturdy microwavable plastics, linings for metal food-and-beverage containers, baby bottles, and numerous other products. When consumed, the chemical can mimic the effects of estrogen. Previous tests had found that bisphenol-A can leach into food and water and that it's widely prevalent in human blood.
The newfound contribution of the chemical to insulin resistance, a precursor to diabetes, might partially explain the global epidemic of that disease, says Angel Nadal of Miguel Hernández University of Elche in Spain, who led the new study.
The finding is a "wake-up call" for public health researchers who are concerned by the prevalence of diabetes, comments developmental biologist Frederick vom Saal of the University of Missouri–Columbia.
Earlier test-tube studies had suggested that bisphenol-A makes pancreatic cells secrete the glucose-regulating hormone insulin. To investigate this effect in live animals, Nadal and his colleagues injected adult male mice with pure corn oil or with oil containing either bisphenol-A or an equal amount of the natural female sex hormone estradiol. Animals received as many as eight shots over 4 days.
Within 30 minutes of an injection, animals receiving either the sex hormone or bisphenol-A had abnormally low concentrations of glucose in their blood, Nadal's team reports in the January Environmental Health Perspectives. The chemicals acted on recently discovered estrogen receptors on pancreatic cells' surfaces to boost the cells' secretion of insulin, the researchers determined.
Repeated exposure to either bisphenol-A or the natural estrogen over several days produced insulin resistance, a pre-diabetic state in which tissues lose their sensitivity to normal concentrations of insulin, Nadal's group says. Estrogen receptors in the pancreatic-cell nucleus appear to contribute to this gradual effect.
So, receptors both in the cell nucleus and on the surface could contribute to insulin resistance and diabetes, Nadal says.
This risk could add to or elucidate already documented health effects of bisphenol-A. Animal studies have suggested that exposure to the chemical early in life causes obesity, says Ana M. Soto of Tufts University School of Medicine in Boston.
Furthermore, bisphenol-A exposure might contribute to gestational diabetes in women, in whom insulin resistance often increases during pregnancy, says Jerry Heindel of the National Institute of Environmental Health Sciences in Research Triangle Park, N.C.
Inside cells' nuclei, bisphenol-A is less potent than the natural sex hormone, says vom Saal. But the new work shows that at the surface of pancreatic cells, the compounds have the same potency, he notes. Doses of bisphenol-A considered by the Environmental Protection Agency to have no adverse effect led to insulin resistance in the mouse study.
Makes me wonder.
Insulin resistance = Type 2 diabetes, I believe....
Not me.
Well, it might help if doctors would test your estrogen levels .....American women especially, are "over-estrogenized" at or near menopause.....what they need more than estrogen is Progesterin and Testosterone.....but, getting a GP who works for a "medical corporation" to do that is nye impossible.....they'd rather just treat with drugs, IMHO.....(been there....)
Trying to be careful here but biphenal-A has been linked to a number health problems. Just Google xenoestrogens and weed through the tin foil hat information!
Hmmmmm, this is no time to switch to a plactic foil hat...
Not quite true.
Insulin resistance often leads to Type 2 diabetes. It is considered enough of an indicator that the life insurance rates for those with IR are almost the same as those with Type 2 diabetes.
My doctor told me I was a 'good candidate' for type-2 diabetes.
And mother's milk contains cancerous cells. Hamburgers cause cancer. We're all gonna die one day.
Why is the bisphenol-A present in PC?
Plasticizer?
Release agent?
Polymerization biproduct?
De-polymerization biproduct?
"Bisphenol A is the basic building block from which polycarbonate plastics are assembled."
Ain't google grand?
Perhaps this explains why my cat, Oslo, has diabetes...he never allows himself to be seen in public without a fresh bottle of Evian® and will only eat of fresh, clean plastic plates...
I thought it was due to all of the super sized big mac meals from McDonalds that Americans eat?
ping
Yeah, but I don't want to die from plastic.
Lots of stuff on how the estrogenization has produced prostate problems for men and breasts on too young females.
CAPITALISM CAUSES CANCER! (and diabetes, too)
"So, receptors both in the cell nucleus and on the surface could contribute to insulin resistance and diabetes, Nadal says."
The effect is reversable. Also, the concentraction given in the study had a pharmaceutical effect. You don't get a pharmaceutical effect from using plastic food contact items. More luttite junk science.
Ahem. I did a Google on Luttite Junk Science, and this is what I got. Looks like you used a junk word, huh?
LOL. Yes, I tend to make those phonetic spellings. Unless I see it, I won't catch it.
Good point. I was more focused on the fact that this wasn't a Type 1 diabetes thing -- although, if they're correct about this it might help to identify some environmental trigger for that, too.
Okay, as you were.
It's pretty interesting, if you can deal with the style.
Besides the endocrine-disrupting chemicals that are the usual subjects, I wonder what effect oral contraceptives containing estrogens have had on insulin resistance and type 2 diabetes?
From the link in my post, the max a person could get is 8000 times less if they ate "tons" of food. I didn't calculate the amount of food necessary to eat in order to get 1/2 the dose the study used. The folks in the link did that. Here's how they put it:
"Stated another way, an average adult consumer would have to ingest more than 600 kilograms (about 1,300 pounds) of food and beverages in contact with polycarbonate every day for an entire lifetime to exceed the level of BPA that the U.S. Environmental Protection Agency has set as safe."
That's almost 3/4 ton of food a day to get 1/2 the dose in the study. Also, what the study doesn't mention is that this is reversible. When the intact stops, the system goes back to normal. There's no permanent effect, because it's simply a molecule reversibly binding to a receptor.
From the link:
" Using these results, the estimated dietary intake of BPA from polycarbonate is less than 0.0000125 milligrams per kilogram body weight per day." That's if polycarbonate is used. Most drinks come in PET(polyethylene terepthalate) bottles. Polycarbonate dishes would suck, because they're too soft and would never get clean. In general, polycarbonate is an engineering plastic used where toughness is required. Bisphenol A also is used in epoxy resins.
"I wonder what effect oral contraceptives containing estrogens have had on insulin resistance and type 2 diabetes?"
If pills caused t2 diabetes, you'd of heard about it a long time ago.
Why is Estrogen such a screwed up hormone? With it, women get all these problems. Without it, they get others (libido problems, hot flashes, etc)
Is the "over-estrogenization" you refer to that is the problem?
how well respected is the journal of "environmental health perspectives"?
great post
I didn't say "caused." Many pills are POPs, i.e. progestin only pills.
I don't have the time to check your link, or any calculations that were mentioned. If you enter estrogen and diabetes into PubMed, you get 1617 citations, 439 of which are review articles.
Adverse drug reaction reporting is voluntary. Combined oral contraceptives, i.e. both an estrogen and progestin component are included, attempt a more physiologic approach. Warning against combined oral contraceptives is relatively, politically incorrect. This is the first paper that I've read that offers an explanation for hyperglycemia secondary to anti-inflammatory steroid pharmacotherapy, e.g. prednisone.
Eekkkkkk!
Do you respect the government?
Environmental Health Perspectives (EHP) is a monthly journal of peer-reviewed research and news on the impact of the environment on human health. EHP is published by the National Institute of Environmental Health Sciences and its content is free online. Print issues are available by paid subscription. They are using gov't logos. Fraud sounds like a dumb idea.
The way I understand it.....women need PROGESTERONE more than they need Estrogen....in later years, at least....actually....they need their hormones "balanced" and that requires lab tests. What happens that causes problems is when a hormone (usually estrogen) overtakes the others......or another hormone, i.e. progesterone drops off, so that estrogen dominates.....which is usually what happens. And, IF there are so many estrogenic products in our lives we can see how estrogen might start dominating and start causing problems.
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