It began with something so mild, she probably thought it would pass within minutes.

Anne Coffman felt a numbness in her toes. No big deal. But it didn't pass.

In time, the numbness gradually spread to her feet, and then her legs. Today, Ms. Coffman is wheelchair-bound and so weak she finds it difficult to feed herself.

When I tell you what common product her condition is linked to, you might be amazed.

But when I tell you about the clumsy attempt to keep it all under wraps, you might start spitting bullets -- I know I did!

Tooth for a tooth

Anne Coffman is one of the 35 million Americans who wear dentures. In an ABC News report, she said she began to feel the numbness in her toes three years after she started using Fixodent.

If that rings a bell, you may recall a study I told you about a couple of years ago. Researchers examined four subjects with neurological abnormalities. Each subject used large amounts of denture cream, and each turned out to have very high blood levels of zinc.

When zinc levels are too high, copper levels drop, and the risk of neurological problems increases sharply.

But here's the curve ball: That study was finished in 2006, but wasn't published until 2009. Why the delay in this information that could help millions of people avoid neurological damage?

ABC reports that the authors of the study say the results were delayed by Dr. Kenneth Shay, a dentist in Ann Arbor, Michigan.

Dr. Shay was asked to conduct a peer review of the study -- a process that's supposed to ensure that the study design is sound, results are accurate, conclusions are logical, etc.

But in Dr. Shay's review, he claimed the link between neurological symptoms and denture cream use was "little more than speculation." The authors even admit that Dr. Shay's recommendations caused them to "water down" the findings.

Then, earlier this year, the first shoe dropped...

ABC reported that Dr. Shay never disclosed that he was a paid consultant for Proctor & Gamble (the maker of Fixodent) at the time of the peer review -- an OUTRAGEOUS ethical offense.

And the second shoe...

ABC News also reports that Dr. Shay sent drafts of the study to P&G -- another huge ethical blunder, which he himself acknowledged in an e-mail at the time: "Please be circumspect because, as a reviewer, I'm not supposed to be passing an unpublished manuscript around."

The worst part of this sorry mess is the delay of publication. Who can say how many denture-wearers experienced further harm while the study was stalled in peer review?

Since publication of the study, Fixodent labels now carry warnings about potential zinc overload from excessive use. The makers of Poligrip went one better and removed zinc from their products last year.

But all of that is too little too late for Anne Coffman and many others who suffered while Dr. Shay served his corporate benefactors.

If you know someone who has dentures, give them a heads up about this risk. Longtime users of Fixodent and other zinc-containing denture creams might never spot the new warnings and go right ahead using dangerously large amounts.

Related article of interest:

Is Copper Making You Crazy? A Closer Look at Copper Toxicity

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