The flap over gum goop

Paralysis, numbness, tingling, muscular weakness, copper deficiency, bone marrow failure and subsequently, anemia... what can these symptoms have in common? According to a study* by the University of Texas, Colorado U. and the Mayo clinic: Polident and Fixodent. More specifically, zinc poisoning.

Thusfar, doctors are being diplomatic, counseling users to follow use directions and apply in moderation but, quoting the U.T. study via MSNBC•, "Based on patients' denture cream use, the researchers estimate that they were exposed to at least 330 mg of zinc daily, far more than the recommended daily allowance of 8 mg for women and 11 mg for men. The National Academy of Sciences stated in 2001 that the largest daily tolerable zinc intake is 40 mg." That's a lot of over-gooping.

You can buy a subscription to Neurology* and read the study in its original context (the abstract is free) and entirety or you can catch the highlights from MSNBC†. I found this company response†† interesting, "The amount of zinc an average denture adhesive user would ingest from daily usage of Fixodent is less than the amount of zinc in a daily multi-vitamin; less than 6 oysters (fried or raw); comparable to 6 oz. beef tenderloin." (Scroll down to the bottom; it's in answer to a doctor's report.) These seem to be the closest that either company will come to releasing numbers of their own and there are none yet from the FDA, to my knowledge.

Not sure whether the folks at P&G (Fixodent), meant the net amount from an average multivitamin or the absorbed amount, as some sewer workers have been able to read the name from them later. Sorry, hope you weren't eating.

From the original report's abstract, published in Neurology, a medical journal, "Results: Zinc concentrations ranging from about 17,000 to 34,000 µg/g were identified in Fixodent and Poli-Grip denture creams. Serum zinc levels improved in three patients following cessation of denture cream use. Copper supplementation resulted in mild neurologic improvement in two patients who stopped using denture cream. No alternative source of excess zinc ingestion or explanation for hypocupremia was identified.

Conclusion: Denture cream contains zinc, and chronic excessive use may result in hypocupremia and serious neurologic disease. "
"From the Departments of Neurology (S.P.N., L.A.L, G.I.W., J.R.T.) and Clinical Sciences (L.S.H., J.R.), University of Texas Southwestern Medical Center, Dallas; the Department of Pathology (P.J.B.), University of Colorado Health Sciences Center; and the Department of Laboratory Medicine and Pathology (M.F.B., J.A.B.), Mayo Clinic, Rochester, MN."
Seems like an impressive set of checks and balances.

I did find an interesting paper on the effect of copper deficiency in mice.**
"Dietary copper deficiency (CuD) leads to cardiomyopathy in experimental animal models (1–5). Copper depletion–induced cardiomyopathy is characterized by concentric cardiac hypertrophy such as occurs in the pressure overloaded heart (4, 6). Although CuD heart hypertrophy may be initially an adaptive response to a stress stimulus, which normalizes wall tension, further progression leads to impaired cardiac muscle function and heart failure (7)." You can download a PDF to read the rest for yourself. The damage can be repaired by reintroduction of dietary copper (don't tell the lawyers).

*Original study
http://www.neurology.org/cgi/content/abstract/71/9/639

†Highlights, free.
http://www.msnbc.msn.com/id/26564090/

††Corporate reply
http://bmartinmd.com/2008/08/zinc-in-excess-denture-cream-m.html

**Dietary Copper Restriction-Induced Changes in Myocardial Gene Expression and the Effect of Copper Repletion
http://www.ebmonline.org/cgi/content/abstract/229/7/616
http://www.ebmonline.org/cgi/reprint/229/7/616

Several law firms are also making a case of their own
www.yourlawyer.com/topics/overview/Denture-Cream-Zinc-Poisoning&title=Denture%20Cream%20Zinc%20Poisoning

http://www.schmidtandclark.com/Dentures/

http://neuropathy-zinc-toxicity-dental-cream.com

Dietary copper sources
http://www.naturalhealthtechniques.com/diet_nutrition/copper.htm
www.dietbites.com/Diet-Articles-8/copper.html

FYI, any info quoted here is for review purposes only and meant to point the way to highly qualified professionals. I am not now, nor was I ever a doctor, lawyer or denture product consumer.

Mood music - Mandelgroove by The Blue Man Group