H E A LT H
Mind your teeth: Dental
fillings may harm your brain,
heart and kidney
P
eople who advise you to take care of your teeth
do not do it for nothing. According to a new study,
people with more than eight dental fillings are at
an increased risk of brain, heart and kidney damage,
because of more mercury in their blood (about 150%
more than usual). Dental surface restorationsor, commonly known as dental fillings, is composed of dental
amalgam — a mixture of mercury, silver, tin and other
metals. The research by University of Georgia in the US,
analysed data from nearly 15,000 individuals and is the
first to demonstrate a relationship between dental fillings
and mercury exposure.“Tooth decay is one of the most
prevalent chronic diseases. I think a majority of people
have experienced dental fillings, but the kind of materials the dentist uses is not something that is really discussed,” said lead author Lei Yin, a scientist at University of Georgia. Mercury exposure from dental fillings is
not a new concern, but previous studies were inconsistent and limited said Xiaozhong Yu, assistant professor
at University of Georgia. “This study is trying to provide
the most accurate levels of exposure, which will form the
scientific basis to make future risk assessment,” said Yu.
It was the first study to control for age, education, ethnicity, race, gender, smoking and seafood consumption,
which also contributes to mercury levels in the body, he
said.Researchers further analysed exposure by specif-
ic types of mercury and found a significant increase in
methyl mercury, which is the most toxic form, related to
dental fillings. Yu said this result suggests the human
gut microbiota, a collection of microorganisms living in
the intestines, may transform different types of mercury.
Dental amalgam has been the go-to dental filling material for more than 150 years, because it is affordable and
durable. However, about half of the compound contains
mercury, a heavy metal known to be toxic at high levels,
causing brain, heart, kidney, lung and immune system
damage.New research suggests that methyl mercury
may cause damage even at low levels. “As toxicologists,
we know that mercury is poison, but it all depends on
the dose. If you have one dental filling, maybe it is ok.
But if you have more than eight dental filings, the potential risk for adverse effect is higher,” Yu said. People
with numerous dental fillings who are also exposed to
mercury from other sources, such as seafood or work
environments, are most at risk. The results show that
individuals with more than eight fillings had about 150%
more mercury in their blood than those with none. The
study also looked at dental composite resins, a mercuryfree alternative for dental fillings that can release small
amounts of bisphenol A which may cause developmental or reproductive damage. The research appears in the
journal Ecotoxicology and Environmental Safety.
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