Science and Health and Radical
Centrism
The following article, while not directly RC
relevant, nonetheless may have
some interest here for its implications. We live in a
globalizing age, if we aren't
already global, and, thanks to the Internet, we live in a
time of vast choices,
including choices to accept and use traditional
medicines.
Something that Jonathan Haidt said during his lecture on
C-Span was addressed to
the liberals in his audience. They had just chuckled
about the 'superstitious' beliefs
of traditionalist Christians. At this Haidt ( pronounced
"height" ) asked the audience
if any of them had ever visited a natural foods store
recently. For in these clearly
liberal-in-inspiration shops are not only foods to eat
but a plethora of claims to digest
--claims for virtually magical powers for certain herbs,
claims about toxins and
detoxification regimens, claims about vegetarianism,
claims about the environment
and organics, and on and on, most of which are
questionable and
some of which are completely bogus.
Here is a look at traditional Chinese medicines.
This leads to other questions. What about additional
culture-based ( which may well
mean religion based ) practices that may have a
connection to health ?
It now is fairly well established that any kind of
fasting longer than, say,
a day or so, has adverse health effects. It also is
clear that customs which
promote endogamy --marriage within a cultural group,
sometimes narrowly
defined to mean clan subgroups-- have deleterious
consequences.
Conversely, some practices are good for one's health.
This seems to be true
for some forms of yoga, maybe most forms of yoga, but is
it true for all forms
of yoga ? And what about food avoidance ? We also know
that, given
historic problems with pork because of difficulty in
"keeping" it over any
significant period of time, it was best policy to avoid
pork eating unless the
animal was consumed shortly after slaughter. Mozart, for
instance, seems
to have died because of food poisoning caused by eating
spoiled pork.
But are important nutrients sacrificed by pork avoidance
? Maybe not,
but it is worth asking the question. And asking
something similar
for other food taboos or food preferences.
Then there is Muslim practice of "covering" for women.
What does this do for
women's vitamin needs ? With limited exposure to
sunlight, what are the health costs
for them ? Not to mention the social costs associated
with strict gender segregation.
In short, we are also entering an age when traditional
values and practices are coming
under increasing scrutiny by scientists and other
researchers. It would seem to be
a safe bet that some traditions won't pass the test. It
would also seem to be true,
as also discussed in the article, that some traditional
customs, remedies, etc,
will be validated as really good for you and, whatever
religious or national
origin, will spread all over the world.
Billy
from the site :
Science / aaas.org
Dangers
of Chinese Medicine Brought to Light by DNA Studies
Traditional Chinese medicine (TCM) is enjoying
increasing popularity all over the world. But two
molecular genetics studies published this week show that
the trendy treatments can be harmful, as well. The
papers focus attention on the fact that not all of their
ingredients are listed, or even legal, and that some can
cause cancer.
"These two studies show very clearly how dangerous the
products of TCM can be," says Fritz Sörgel, the head of
the Institute for Biomedical and Pharmaceutical Research
in Nuremberg, Germany, who was not involved in the work.
"The public needs to be better informed about these
dangers."
Hundreds of millions of dollars are spent on TCM
products each year—a growing portion of it on the
Internet—and some scientists are looking at these
preparations hoping to discover new pharmacological
substances. Many would like to emulate the success of Tu
Youyou, the Chinese scientist who isolated artemisinin,
now the world's most important malaria drug, from an
ancient Chinese medicine. Tu won a Lasker award last
year and is rumored to be a Nobel candidate.
But critics have long warned that some mixtures can
also contain naturally occurring toxins, contaminants
like heavy metals, added substances such as steroids
that make them appear more effective, and traces of
animals that are endangered and trade-restricted.
Now, researchers at Murdoch University in Australia
have investigated the problem using modern sequencing
technology. The team, based at the university's
Australian Wildlife Forensic Services and Ancient DNA
Laboratory in Perth, analyzed 15 samples of traditional
Chinese medicine seized by Australian border officials.
"We took these traditional preparations, smashed them
to pieces, and extracted the DNA from the powder,"
explains molecular geneticist Michael Bunce. The
scientists then fished out copies of two specific genes,
trnL, a chloroplast gene common to all plants,
and 16srRNA, conserved among plants and animals,
and multiplied and sequenced them. By comparing the
sequences to those in genetic databases, they could
pinpoint the animals and plants used to make the
medicine. "Sometimes we really struggled to assign a
particular DNA to a particular species," Bunce says. But
as genetic databases expand, this should become easier.
Some products contained material from animals
classified as vulnerable or critically endangered, such
as the Asiatic black bear and the Saiga antelope—just as
the producers claimed. But often, the
medicine also harbored ingredients not mentioned on
the packaging, the team reports online today in PLoS
Genetics. "For example, a product labeled 100
percent Saiga antelope contained considerable quantities
of goat and sheep DNA," Bunce writes.
"Using DNA to identify the animal species and thus
prove illegal trading is very elegant," says Dietmar
Lieckfeldt, who works in molecular forensics at the
Leibniz Institute for Zoo and Wildlife Research in
Berlin, Germany. Identifying animals by their DNA has
been possible for a while, he says, but the
next-generation sequencing technology makes it possible
to nail different species in a mixture very quickly.
In the herbal preparations, Bunce and his colleagues
found members of 68 different plant families, among them
plants of the genera Ephedra and Asarum.
Both can contain toxic chemicals such as aristolochic
acid, a compound banned in many countries because it
causes kidney disease and cancer of the upper urinary
tract (UUC). While detecting DNA from a certain species
does not mean that a toxin produced by that plant is
present, chemical analysis of one of the four samples
containing Asarum DNA did turn up aristolochic
acid.
The threat posed by aristolochic acid is also
highlighted in a paper published in the Proceedings
of the National Academy of Sciences on Monday. The
researchers, led by pharmacologist Arthur Grollman of
Stony Brook University, focused on Taiwan, the country
with the highest rate of UUC in the world. A previous
analysis had shown that roughly one-third of the
Taiwanese population consumed herbs likely to contain
aristolochic acid.
The scientists sequenced the tumors of 151 patients
with UUC. Among patients with characteristic mutations
in the important tumor-suppressor gene TP53—which
make people more vulnerable to cancer—84% also showed a
known molecular signature of exposure to aristolochic
acid, they found. The study provides compelling evidence
that aristolochic
acid is a primary cause of UUC in Taiwan, the
authors argue.
Bunce and his colleagues also found DNA from plant
families known to contain medicinally important species
that could pose risks when used in combination with
other drugs, as well as DNA from soybean and plants of
the cashew family, which can contain allergens. "This
just shows that the ingredients in these preparations
aren't accurately declared," Bunce argues. Indeed, says
Sörgel, the studies show that partaking in traditional
Chinese herbal medicine is a gamble: "We just don't know
enough about it."
