Teeth whiteners damage the enamel

NEW YORK (Reuters Health) - Teeth bleaching products for home use may minimally reduce the surface hardness of tooth enamel and enamel's ability to "bounce back" from normal wear and tear, a laboratory study suggests.

Still, "the public should not be alarmed of the bleaching process," said Dr. Shereen S. Azer, at The Ohio State University College of Dentistry in Columbus.

"In reality -- or clinically speaking -- these effects may not be detectable," Azer told Reuters Health.

Moreover, Azer said, "human enamel has been shown to heal itself and 'remineralize' over time, meaning it has the ability to restore back the levels of surface calcium that has been lost due to bleaching." This is particularly evident with subsequent fluoride treatments and use of fluoride toothpastes.

Azer and colleagues used a nanometer scale - the equivalent of one over a billionth of a meter - to measure the hardness and elasticity of tooth enamel both before and after laboratory exposures to over-the-counter teeth bleaching solutions.

The researchers exposed 50 human tooth samples to 2 types of whitening strip and 3 types of nightguard home bleaching systems,

Ten tooth samples each underwent bleaching regimens according to either the 3-week or 10-day manufacturer recommended treatment protocol. The 5 remaining tooth samples served as unbleached "controls."

Compared with before bleaching and versus unbleached controls, the bleached enamel showed significant decreases in hardness on the nanometer scale, the investigators report in the Journal of Dentistry.

The researchers also observed a significant decrease in enamel elasticity in most bleached tooth samples compared with unbleached controls.

More study into the long term effects of bleaching agents and remineralization of tooth enamel would be worthwhile, the researchers conclude.

SOURCE: Journal of Dentistry, March 2009.



© Thomson Reuters 2009 All rights reserved


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NEW YORK (Reuters Health) - Teeth bleaching products for home use may minimally reduce the surface hardness of tooth enamel and enamel's ability to "bounce back" from normal wear and tear, a laboratory study suggests.

Still, "the public should not be alarmed of the bleaching process," said Dr. Shereen S. Azer, at The Ohio State University College of Dentistry in Columbus.

"In reality -- or clinically speaking -- these effects may not be detectable," Azer told Reuters Health.

Moreover, Azer said, "human enamel has been shown to heal itself and 'remineralize' over time, meaning it has the ability to restore back the levels of surface calcium that has been lost due to bleaching." This is particularly evident with subsequent fluoride treatments and use of fluoride toothpastes.

Azer and colleagues used a nanometer scale - the equivalent of one over a billionth of a meter - to measure the hardness and elasticity of tooth enamel both before and after laboratory exposures to over-the-counter teeth bleaching solutions.

The researchers exposed 50 human tooth samples to 2 types of whitening strip and 3 types of nightguard home bleaching systems,

Ten tooth samples each underwent bleaching regimens according to either the 3-week or 10-day manufacturer recommended treatment protocol. The 5 remaining tooth samples served as unbleached "controls."

Compared with before bleaching and versus unbleached controls, the bleached enamel showed significant decreases in hardness on the nanometer scale, the investigators report in the Journal of Dentistry.

The researchers also observed a significant decrease in enamel elasticity in most bleached tooth samples compared with unbleached controls.

More study into the long term effects of bleaching agents and remineralization of tooth enamel would be worthwhile, the researchers conclude.

SOURCE: Journal of Dentistry, March 2009.



© Thomson Reuters 2009 All rights reserved

Poor fertility and a chance...one more

For conceiving, both partners need to take UNrefined Wheatgerm Oil 3x daily at one tablespoon levels -Craig

Poor Fertility Chances (PFCs)

January 30, 2009 by Karla

A study from the University of California has found that women with high levels of perfluorinated compounds (PFCs) in their blood tended to take longer to conceive than women with lower PFC levels.

PFCs are a family of fluorine-containing chemicals designed to make fabrics stain resistant and are found in food packaging, pesticides, carpets and cosmetics. There are a number of health concerns regarding two types of PFCs in particular - perfluorooctanoic acid (PFOA) which is used to make Teflon products and perfluorooctane sulfonate (PFOS), which was used for some time to make Scotchgard products. PFOA causes liver, pancreatic, testicular and mammary gland tumours in lab animals and is therefore a likely carcinogen for humans. PFOS causes liver & thyroid cancer in rats.

The US study showed that women exposed to PFCs may have lower fertility and irregular menstrual cycles and PFCs can also affect sperm quality in men.

PFCs can linger in our bodies for over four years and so avoidance is the best policy – steer clear of grease-proof and oiled packaging, avoid stain-resistant treatments on furniture and carpets and try to avoid toiletries containing any ingredients named ‘fluoro’ or ‘perfluoro’, common in dental floss, nail polish and eye make-up. Always go for natural alternatives where possible!

Law cholesterol linked to depression and suicide

(NaturalNews) The next time you stop in for your annual check-up with your doctor, chances are you'll be checking on your cholesterol levels. With fears spiked about having high cholesterol, even those in the low-risk categories are monitoring their levels religiously. After all, there's nothing like the merit badge of a low cholesterol reading. It's good enough to put a big, bright smile right across your faceâ€"or it may just drive you into depression. That's right. Those charmingly low numbers may be the cause behind depression, anxiety, violence and even suicide.

This is hardly an extremist idea fed by a few confused souls. Just take a look in the British Medical Journal published in September of 1996, where a French study looked at over 6,000 men. The study revealed that men with low cholesterol were three times more likely to commit suicide. A similar study at Payne Whitney Clinic in New York showed a similar result: when dividing men into four groups based on cholesterol levels, suicide risk doubled in the group with the lowest levels.

Equally as disturbing is the link between low cholesterol and violent, impulsive behavior. Dr. Vivian Mitropoulou and her colleagues at Mount Sinai School of Medicine in New York examined 42 patients with personality disorders. Low cholesterol was a strong indicator of irrationally aggressive behavior.

Just one of the many studies linking low cholesterol to deep depression came from Finland's National Public Health Institute, where a study of almost 30,000 people showed men with lower cholesterol readings were the most likely to suffer from crippling depression.

All of these disorders may be explained by low serotonin levels, which are often connected to violent and suicidal behavior. Dr. Beatrice Golomb from The University of California looked at studies linking low cholesterol to violence. She points out that studies which placed monkeys on a diet low in fat and cholesterol suffered from dramatically lower serotonin levels. These low-serotonin monkeys exhibited climbing aggression and violence.

Of course, these findings aren't enough to convince most doctors to overlook other evidence that points toward cholesterol causing health problems. After all, they need to keep writing prescriptions for those cholesterol-lowering drugs that draw in billions of dollars to the industry each year.

Aside from that, these findings are something to seriously consider if you've had a history of depression or violence and your cholesterol levels are running low. Your physician may claim these levels are good for your heart, but there's a chance they could be affecting your head.

Jaret, Peter. Can your cholesterol be too low? WebMD.com (2000)

Toxic dental amalgams admitted

FDA Reluctantly Admits Mercury Fillings Have Neurotoxic Effects on Children

David Gutierrez
Wednesday, Dec 03, 2008
http://www.naturalnews.com/024993.html


For the first time, the FDA has issued a warning that the mercury contained in silver dental fillings may pose neurological risks to children and pregnant women.

“Dental amalgams contain mercury, which may have neurotoxic effects on the nervous systems of developing children and fetuses,” reads a statement that has been added to the agency’s Web site. “Pregnant women and persons who may have a health condition that makes them more sensitive to mercury exposure, including individuals with existing high levels of mercury bioburden, should not avoid seeking dental care, but should discuss options with their health practitioner.”

The warning was one of the conditions that the FDA agreed to in settling a lawsuit filed by several consumer health groups.

“Gone, gone, gone are all of FDA’s claims that no science exists that amalgam is unsafe,” said Charles Brown, a lawyer for Consumers for Dental Choice, one of the plaintiffs.

“It’s a watershed moment,” said Michael Bender of the Mercury Policy Project, another plaintiff.

Mercury is a well-known neurotoxin that can cause cognitive and developmental problems, especially in fetuses and children. It can also cause brain and kidney damage in adults.

So-called dental amalgams, or fillings made with a mix of mercury and other metals, have been used since the 1800s. Although it is known that small amounts of mercury are vaporized (and can be inhaled) when the fillings are used to chew food, and though Canada, France and Sweden have all placed restrictions on the use of mercury fillings, the FDA has always insisted that amalgams are safe.

(ARTICLE CONTINUES BELOW)



Dental amalgams are considered medical devices, regulated by the FDA.

Even the FDA’s new warning stops short of admitting that dental amalgams are dangerous for the general population. Instead, it focuses on the same population that has already been warned to limit mercury exposure by consuming less seafood: children and pregnant women. The FDA says it does not recommend that those who already have mercury fillings get them removed.

Millions of people have received amalgam fillings, although their popularity has dropped off in recent years. Currently, only 30 percent of dental fillings contain mercury - the rest are tooth-colored resin composites made from glass, cement and porcelain. These alternative fillings are more expensive and less durable than amalgam, however.

In 2002, the FDA began a regulatory review of amalgam that was expected to be complete within a few years. In 2006, with the review still incomplete, an independent FDA advisory panel of doctors and dentists rejected the agency’s position that there is no reason for concern about the use of amalgam. While the panel agreed that the majority of people receiving such fillings would not be harmed, panel members expressed concern for the health of certain sensitive populations, including children under the age of six.

The panel recommended that the FDA conduct further studies on the risks to children from dental amalgam, and that it consider a policy of informed consent for children and pregnant: that is, warning those groups of the risks associated with the fillings before installing them.

Part of the lawsuit centered on the FDA’s failure to respond to these recommendations in a timely fashion.

“This is your classic failure to act,” federal judge Ellen Segal Huvelle told the agency.

As part of the lawsuit settlement, the FDA must reach a final decision on the regulation of amalgam by July 28, 2009.

“This court settlement signals the death knell for mercury fillings,” Brown predicted.
But J.P. Morgan Securities analyst Ipsita Smolinski disagreed, saying that the FDA is unlikely to ban amalgam entirely

“We do believe that the agency will ask for the label to indicate that mercury is an ingredient in the filling, and that special populations should be exempt from such fillings, such as: nursing women, pregnant women, young children, and immunocompromised individuals,” Smolinski said

Blue light and anti-cancer therapy

Blue Light Used To Harden Tooth Fillings Stunts Tumor Growth

http://www.sciencedaily.com/releases/2008/...80624110831.htm


ScienceDaily (June 28, 2008) — A blue curing light used to harden dental fillings also may stunt tumor growth, Medical College of Georgia researchers say

"The light sends wavelengths of blue-violet light to the composite, which triggers hardening," says Alpesh Patel, a rising MCG School of Dentistry junior. "The light waves produce free radicals that activate the catalyst and speed up polymerization of the composite resin. In oral cancer cells, though, those radicals cause damage that decreases cell growth and increases cell death."

Mr. Patel, who has been working with Dr. Jill Lewis, associate professor of oral biology, Dr. Regina Messer, associate professor of oral rehabilitation and oral biology, and Dr. John Wataha, adjunct professor of oral rehabilitation and oral biology, studied 10 tumor-bearing mice, five treated with the light and five untreated.

He exposed half the mice to the blue light for 90 seconds a day for 12 days. Then the tumors were extracted and each one was split into two sections. Half were used to create slides for tissue analysis, and half were frozen to prepare protein extracts.

Tissue analysis indicated an approximate 10 percent increase in cell suicide, or apoptosis, in the light-treated tumors. The frozen protein extracts revealed a nearly 80 percent decrease in cell growth in the light-treated tumors.

"The decrease in cell growth, combined with increased apoptosis, helps explain why the tumors didn't grow as much because you have cells that aren't dividing and you have cells that are committing suicide," Mr. Patel says.

Dr. Lewis predicts treating the tumors with blue light sooner will increase the rate of apoptosis, possibly preventing the tumor from ever becoming measurable and easing treatment.

"One desirable feature we've observed with the blue light is that non-cancerous cells appear unaffected at light doses that kill tumor cells," says Dr. Lewis. "We're thinking that some day, blue light therapy may serve as an adjunct to conventional cancer therapy. Patients may, therefore, receive lower doses of chemotherapy, which would decrease the adverse effects most cancer patients experience from standard chemotherapy regimens."

Mr. Patel presented his findings at the 2008 American Association for Dental Research Student Research Group DENTSPLY/Caulk competition, winning third place in the basic science category. He and rising junior MCG School of Dentistry student Beth Rainwater were two of only seven students nationwide to be selected for the competition.


--------------------------------------------------------------------------------

Adapted from materials provided by Medical College of Georgia, via EurekAlert!, a service of AAAS.

Meditation and yoga's benefits

Meditation, Yoga Might Switch Off Stress Genes

By Amanda Gardner
HealthDay Reporter
Wednesday, July 2, 2008; 12:00 AM
http://www.washingtonpost.com/wp-dyn/conte...8070200973.html


WEDNESDAY, July 2 (HealthDay News) -- Researchers say they've taken a significant stride forward in understanding how relaxation techniques such as meditation, prayer and yoga improve health: by changing patterns of gene activity that affect how the body responds to stress.

The changes were seen both in long-term practitioners and in newer recruits, the scientists said.

"It's not all in your head," said Dr. Herbert Benson, president emeritus of the Benson-Henry Institute for Mind/Body Medicine at Massachusetts General Hospital and an associate professor of medicine at Harvard Medical School. "What we have found is that when you evoke the relaxation response, the very genes that are turned on or off by stress are turned the other way. The mind can actively turn on and turn off genes. The mind is not separated from the body."


One outside expert agreed.

"It's sort of like reverse thinking: If you can wreak havoc on yourself with lifestyle choices, for example, [in a way that] causes expression of latent genetic manifestations in the negative, then the reverse should hold true," said Dr. Gerry Leisman, director of the F.R. Carrick Institute for Clinical Ergonomics, Rehabilitation and Applied Neuroscience at Leeds Metropolitan University in the U.K.

"Biology is not entirely our destiny, so while there are things that give us risk factors, there's a lot of 'wiggle' in this," added Leisman, who is also a professor at the University of Haifa in Israel. "This paper is pointing that there is a technique that allows us to play with the wiggle."

Benson, a pioneer in the field of mind-body medicine, is co-senior author of the new study, which is published in the journalPLoS One.

Benson first described the relaxation response 35 years ago. Mind-body approaches that elicit the response include meditation, repetitive prayer, yoga, tai chi, breathing exercises, progressive muscle relaxation, biofeedback, guided imagery and Qi Gong.

"Previously, we had noted that there were scores of diseases that could be treated by eliciting the relaxation response -- everything from different kinds of pain, infertility, rheumatoid arthritis, insomnia," Benson said.

He believes that this study is the first comprehensive look at how mind states can affect gene expression. It also focuses on gene activity in healthy individuals.

Benson and his colleagues compared gene-expression patterns in 19 long-term practitioners, 19 healthy controls and 20 newcomers who underwent eight weeks of relaxation-response training.

More than 2,200 genes were activated differently in the long-time practitioners relative to the controls and 1,561 genes in the short-timers compared to the long-time practitioners. Some 433 of the differently activated genes were shared among short-term and long-term practitioners.

Further genetic analysis revealed changes in cellular metabolism, response to oxidative stress and other processes in both short- and long-term practitioners. All of these processes may contribute to cellular damage stemming from chronic stress.

Another expert had a mixed response to the findings.

Robert Schwartz, director of the Texas A&M Health Science Center's Institute of Biosciences and Technology in Houston, noted that the study was relatively small. He also wished that there had been more data on the levels of stress hormones within the control group, for comparison purposes.

However, Schwartz called the study "unique and very exciting. It demonstrates that all these techniques of relaxation response have a biofeedback mechanism that alters gene expression."

He pointed out that the researchers looked at blood cells, which consist largely of immune cells. "You're getting the response most probably in the immune cell population," Schwartz said.

"We all are under stress and have many manifestations of that stress," Benson added. "To adequately protect ourselves against stress, we should use an approach and a technique that we believe evokes the relaxation response 20 minutes, once a day."

More information

There's more on meditation at the U.S. National Center for Complementary and Alternative Medicine.

SOURCES: Herbert Benson, M.D., president emeritus, Benson-Henry Institute for Mind/Body Medicine, Massachusetts General Hospital, and associate professor of medicine, Harvard Medical School, Cambridge, Mass.; Gerry Leisman, M.D., Ph.D., director, F.R. Carrick Institute for Clinical Ergonomics, Rehabilitation and Applied Neuroscience and professor, neuroscience, Leeds Metropolitan University, U.K. and professor, University of Haifa, Israel; Robert Schwartz, Ph.D., director, Texas A&M Health Science Center Institute of Biosciences and Technology, Houston;PLoS One

Toxic dental amalgam mercury fillings!

US issues health warning over mercury fillings

They're in millions of mouths worldwide, but have been linked to heart disease and Alzheimer's. Now a report concedes they may have a toxic effect on the body

By Geoffrey Lean, Environment Editor
Sunday, 29 June 2008
http://www.independent.co.uk/life-style/he...ngs-856582.html


Amalgam dental fillings – which contain the highly toxic metal mercury – pose a health risk, the world's top medical regulatory agency has conceded.

After years of insisting the fillings are safe, the US government's Food and Drug Administration (FDA) has issued a health warning about them. It represents a landmark victory for campaigners, who say the fillings are responsible for a range of ailments, including heart conditions and Alzheimer's disease.

Earlier this month, in an unprecedented U-turn, the FDA dropped much of its reassuring language on the fillings from its website, substituting: "Dental amalgams contain mercury, which may have neurotoxic effects on the nervous systems of developing children and foetuses." It adds that when amalgam fillings are "placed in teeth or removed they release mercury vapour", and that the same thing happens when chewing.

The FDA is now reviewing its rules and may end up restricting or banning the use of the metal.

Mercury is placed in tens of millions of teeth worldwide each year. About 125 tons of it is used annually in dental treatments in the EU alone. And it was used in eight million fillings (including one million in children and young people) in Britain in 2002-03, the last year for which the British Dental Association (BDA) can produce figures.

The association continues to insist that amalgam is "safe, durable and cost-effective" and "does not pose a risk of systemic disease", though it advises pregnant women to avoid "any dental intervention or medication". However, Norway and Denmark banned mercury from fillings earlier this year. Sweden has cut its use by more than 90 per cent over the past decade, and mercury use is also heavily restricted in Finland and Japan.

Mercury makes up about half of an amalgam filling, where it is mixed with silver and small amounts of copper and tin. The combination – which has now been used for some 150 years – is extremely durable, and its supporters used to stress that it locked in the mercury. They now accept, however, that mercury vapour escapes, is breathed in, and gets into the bloodstream and organs, but they also stress that levels are very low. Opponents argue that the metal accumulates in the body and no safe level is known.

Some research suggests that mercury from dental fillings may be linked to high blood pressure, infertility, fatigue, disorders of the central nervous system, multiple sclerosis and Alzheimer's disease. Dentists have been found to have high levels of mercury in their bodies as well being more susceptible to brain tumours and problems with concentration and manual dexterity.

However, a study that followed 507 Portuguese and American children for seven years after they received amalgam or mercury-free fillings found no differences in the rates of neurological symptoms between the two groups.

Nevertheless, more and more dentists – now some 500 in Britain – are setting up mercury-free practices, and more patients are demanding alternative fillings made of resin and glass.

The alternatives are more expensive and not as strong as amalgam, which leads the defenders of mercury to say that only mercury will do for molars, which carry most of the burden of chewing. And some have released another toxic material, the gender-bending chemical bisphenol A. But the alternatives are getting stronger, and the chemical is being used less in the newer products.

Even the BDA now says that the alternatives "have improved over time", adding: "Trends towards greater use of these materials imply that there is to be a sustained reduction in the use of dental amalgam."