Study confirms increase in wheat gluten disorder Blood
samples from '50s show it isn't just improved diagnosis, and researchers
wonder if diet is a factor.
By JOSEPHINE
MARCOTTY, Star Tribune
Last update: July 1, 2009 - 9:27 AM
A Minnesota study using frozen blood samples taken from Air Force
recruits 50 years ago has found that intolerance of wheat gluten,
a debilitating digestive condition, is four times more common today
than it was in the 1950s.
The findings contradict the prevailing belief
that a sharp increase in diagnoses of wheat gluten intolerance has
come about because of greater awareness and detection, and raises
questions about whether dramatic changes in the American diet have
played a role.
"It's become much more common,"
said Dr. Joseph Murray, the Mayo Clinic gastroenterologist who led
the study. No one knows why, he said, but one reason might be rapid
changes in eating habits and food processing over the last half
century.
"Fifty years is way too fast for human
genetics to have changed," Murray said. "Which tells us
it has to be a pervasive environmental influence."
Researchers at the Mayo Clinic and the University
of Minnesota who conducted the study also found that the recruits
who had the undiagnosed digestive disorder, called celiac disease,
also had a four-fold increase in the risk of death.
Today an estimated one of 100 people suffer
from the inherited disorder, though most of the time people don't
know they have it.
The disease occurs in people whose bodies
cannot digest gluten, a protein found in wheat, rye and barley.
The undigested protein triggers the body's immune system to attack
the lining of the small intestine, causing diarrhea, nausea and
abdominal pain. Though people live with it for many years, over
time it destroys the lining of the small intestine, leading to an
inability to absorb nutrients such as iron and calcium. That, in
turn, causes serious problems, including anemia, osteoporosis and
even infertility.
The only treatment is a gluten-free diet --
no wheat, rye or barley.
Murray said he initiated the study to find
out whether the disease is on the rise, and whether it had long-term
health consequences if undiagnosed and untreated.
He turned to medical archaeology to find the
answers - a treasure-trove of blood samples taken from recruits
at the Warren Air Force base in Cheyenne, Wyo., between 1948 and
1954. At the time, strep infections were raging among the recruits,
mostly young men on their way to fight in the Korean war. Doctors
there drew the samples as part of a study that proved treating the
infections with antibiotics would prevent rheumatic fever, a serious
heart ailment that can follow strep throat.
One of the doctors in that study took some
of the samples with him when he moved to the Cleveland Clinic in
Ohio. When he decided to retire two decades ago, he asked Dr. Edward
Kaplan, a strep specialist at the University of Minnesota, to become
their guardian. The vials were transported in frozen-pizza delivery
trucks to Minneapolis, where they reside today.
"Nobody has anything like it," said
Kaplan. "There are other collections, but none go back this
far."
In 2000 they were used to help resolve an
intense debate among researchers over whether hepatitis C infection
meant certain death, or whether many people could live with it for
years.
Murray used a similar design for the study
on celiac disease, published today in the journal Gastroenterology.
He tested more than 9,133 samples for the antibodies that proved
the recruits had celiac disease; 43, or about one out of 652, had
the disease. He then tested blood samples from groups of men from
Olmsted County, more than 12,000 in all. In an older group of men,
one in 121 tested positive, and in the younger group one in 106
tested positive, an increase of four to four-and-a-half times.
His findings raise questions about why the
number of people with the disease has grown so fast. But rates of
other immune diseases have also increased a lot. One theory is that
modern, clean living, which has resulted in fewer infections, parasites
and microbes in our bodies, causes the immune system to turn on
healthy tissue instead. Or it might be the modern diet, Murray said.
"The types of food we eat now are different,"
he said.
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