Part 1: Genetically Engineered Soybeans
The huge jump in childhood
food allergies in the U.S. is
in the news often, but most
reports fail to consider a link
to a recent radical change
in America’s diet. Beginning in 1996,
bacteria, virus and other genes have
been artificially inserted to the DNA of
soy, corn, cottonseed and canola plants.
These unlabeled genetically modified
(GM) foods carry a risk of triggering
life-threatening allergic reactions, and
evidence collected over the past decade
suggests they are contributing to higher
allergy rates.
Food safety tests are inadequate to protect public health
Scientists have long known that GM
crops might cause allergies. But there are
no tests to prove in advance that a GM
crop is safe. That’s because people aren’t
usually allergic to a food until they have
eaten it several times. “The only definitive
test for allergies,” according to former
FDA microbiologist Louis Pribyl, “is
human consumption by affected peoples,
which can have ethical considerations.”
And it is the ethical considerations of
feeding unlabeled, high-risk GM crops
to unknowing consumers that has many
people up in arms.
The U.K. is one of the few countries
that conduct a yearly evaluation of food
allergies. In March 1999, researchers
at the York Laboratory were alarmed
to discover that reactions to soy had
skyrocketed by 50 percent over the
previous year. Genetically modified soy
had recently entered the U.K. from U.S.
imports and the soy used in the study was
largely GM. John Graham, spokesman for
the York laboratory, said, “We believe this
raises serious new questions about the
safety of GM foods.”
Critics of GM foods often say that
the U.S. population is being used as
guinea pigs in an experiment. But
experiments have the benefit of controls
and measurement. In this case, there is
neither. GM food safety experts point out
that even if someone tried to collect data
about allergic reactions to GM foods,
they would not likely be successful. “The
potential allergen is rarely identified. The
number of allergy-related medical visits
is not tabulated. Even repeated visits due
to well-known allergens are not counted
as part of any established surveillance
system.” Indeed, after the Canadian
government announced in 2002 that they
would “keep a careful eye on the health of
Canadians” to see if GM foods had any
adverse reactions, they abandoned their
plans within a year, saying that such a
study was too difficult.
Genetic engineering may provoke increased allergies to soy
The classical understanding of why a
GM crop might create new allergies is
that the imported genes produce a new
protein, which has never before been
present. The novel protein may trigger
reactions. This was demonstrated in the
mid 1990s when soybeans were outfitted
with a gene from the Brazil nut. While
scientists had attempted to produce a
healthier soybean, they ended up with a
potentially deadly one. Blood tests from
people who were allergic to Brazil nuts
showed reactions to the beans. It was
fortunately never put on the market.
The GM variety that is planted in 89
percent of U.S. soy acres gets its foreign
gene from bacteria (with parts of virus
and petunia DNA as well). We don’t
know in advance if the protein produced
by bacteria, which has never been part
of the human food supply, will provoke
a reaction. As a precaution, scientists
compare this new protein with a database
of proteins known to cause allergies.
The database lists the proteins’ amino
acid sequences that have been shown to
trigger immune responses. If the new GM
protein is found to contain sequences
that are found in the allergen database,
according to criteria recommended by
the World Health Organization (WHO)
and others, the GM crop should either
not be commercialized or additional
testing should be done. Sections of the
protein produced in GM soy are identical
to known allergens, but the soybean
was introduced before the WHO criteria
were established and the recommended
additional tests were not conducted.
If this protein in GM soybeans is
causing allergies, then the situation may
be made much worse by something called
horizontal gene transfer (HGT). That’s
when genes spontaneously transfer from
one species’ DNA to another. While this
happens often among bacteria, it is rare
in plants and mammals. But the method
used to construct and insert foreign
genes into GM crops eliminates many of
the natural barriers that stop HGT from
occurring. Indeed, the only published
human feeding study on GM foods ever
conducted verified that portions of the
gene inserted into GM soy ended up
transferring into the DNA of human gut
bacteria. Furthermore, the gene was
stably integrated and it appeared to
be producing its potentially allergenic
protein. This means that years after
people stop eating GM soy, they may still
be exposed to its risky protein, which is
being continuously produced within their
intestines.
Genetic engineering damaged soy DNA,
creating new (or more) allergens
Although biotech advocates describe the
process of genetic engineering as precise,
in which genes—like Legos—cleanly snap
into place, this is false. The process of
creating a GM crop can produce massive
changes in the natural functioning of
the plant’s DNA. Native genes can be
mutated, deleted, permanently turned
on or off, and hundreds may change
their levels of protein expression. This
collateral damage may result in increasing
the levels of an existing allergen, or even
producing a completely new, unknown
allergen within the crop. Both appear to
have happened in GM soy.
Levels of one known soy allergen,
trypsin inhibitor, were up to 27 percent
higher in raw GM soy. In addition,
although cooking soybeans normally
reduces the amount of this protein, the
trypsin inhibitor in GM varieties appears
to be more heat resistant. Levels in
cooked GM soy were nearly as high as
those found in raw soy, and up to seven
times higher when compared to cooked
non-GM soy. This suggests that this
allergen in GM soy may be more likely to
provoke reactions than when consumed
in natural varieties.
Another study verified that GM
soybeans contain a unique, unexpected
protein, not found in non-GM soy
controls. Moreover, scientist tested
the protein and determined that it
reacted with the antibody called IgE.
This antibody in human blood plays a
key role in a large proportion of allergic
reactions, including those that involve
life-threatening anaphylactic shock. The
fact that the unique protein created by
GM soy interacted with IgE suggests it
might also trigger allergies.
The same researchers measured the
immune response of human subjects
to soybeans using a skin-prick test—an
evaluation used often by allergy doctors.
Eight subjects showed a reaction to GM
soy; but one of these did not also react to
non-GM soy. Although the sample size is
small, the implication that certain people
react only to GM soy is huge, and might
account for the increase in soy allergies
in the U.K.
Increased herbicides on GM crops
may cause reactions
By 2004, farmers used an estimated 86
percent more herbicide on GM soy fields
compared to non-GM. The higher levels
of herbicide residue in GM soy might
cause health problems. In fact, many of
the symptoms identified in the U.K. soy
allergy study are among those related to
glyphosate exposure. [The allergy study
identified irritable bowel syndrome,
digestion problems, chronic fatigue,
headaches, lethargy, and skin complaints,
including acne and eczema, all related
to soy consumption. Symptoms of
glyphosate exposure include nausea,
headaches, lethargy, skin rashes, and
burning or itchy skin. It is also possible
that glyphosate’s breakdown product
AMPA, which accumulates in GM soybeans
after each spray, might contribute to
allergies.]
GM soy might impede digestion,
leading to allergies
If proteins survive longer in the digestive
tract, they have more time to provoke an
allergic reaction. Mice fed GM soy showed
dramatically reduced levels of pancreatic
enzymes. If protein-digesting enzymes
are less available, then food proteins
may last longer in the gut, allowing more
time for an allergic reaction to take place.
Such a reduction in protein digestion due
to GM soy consumption could therefore
promote allergic reactions to a wide
range of proteins, not just to the soy.
No human studies of protein digestion
related to GM soy have been conducted.
Soy linked to peanut allergies
There is at least one protein in natural
soybeans that has cross-reactivity with
peanut allergies. That means for some
people who are allergic to peanuts,
consuming soybeans may trigger a
reaction. While it is certainly possible
that the unpredicted side effects from
genetic engineered soybeans might
increase the incidence of this crossreactivity,
it is unlikely that any research
has been conducted to investigate this.
GM soy was introduced into the U.S.
food supply in late 1996. We are left only
to wonder whether this had an influence
on the doubling of U.S. peanut allergies
from 1997 to 2002.
Eating GM foods is gambling with our health
The introduction of genetically engineered
foods into our diet was done quietly and
without the mandatory labeling that is
required in most other industrialized
countries. Without knowing that GM
foods might increase the risk of allergies,
and without knowing which foods contain
GM ingredients, the biotech industry
is gambling with our health for their
profit. This risk is not lost on everyone.
In fact, millions of shoppers are now
seeking foods that are free from any GM
ingredients. Ohio-based allergy specialist
John Boyles, M.D., says, “I used to test
for soy allergies all the time, but now
that soy is genetically engineered, it is so
dangerous that I tell people never to eat
it—unless it says organic.”
Organic foods are not allowed to
contain GM ingredients. Buying products
that are certified organic or that say non-
GMO are two ways to limit your family’s
risk from GM foods. Another is to avoid
products containing any ingredients
from the seven food crops that have
been genetically engineered: soy, corn,
cottonseed, canola, Hawaiian papaya
and a little bit of zucchini and crook neck
squash. This means avoiding soy lecithin
in chocolate, corn syrup in candies, and
cottonseed or canola oil in snack foods.
Fortunately, the Campaign for Healthier
Eating in America will soon make
your shopping easier. This Consumer
Non-GMO Education Campaign is
orchestrating the clean out of GM
ingredients from foods and the natural
products industry. The campaign will
circulate helpful non-GMO shopping
guides to organic and natural food
stores nationwide. The Campaign will
provide consumers with regular GM food
safety updates that explain the latest
discoveries about why, Healthy Eating
Means No GMOs.
Safe eating.
Author’s note: This article is limited to the
discussion of allergic reactions from GM
soybeans. The evidence that GM corn is
triggering allergies is far more extensive and
will be covered in part 2 of this series.