Maryland Nurse  [Printer-friendly version]
February 1, 2005


[Rachel's introduction: Two nurses examine the issues surrounding
genetically modified foods and conclude that, until more is known, a
precautionary approach is called for.]

By Katie Huffling, RN, BSN and Barbara Sattler, PhD, RN, FAAN

Over the past few years there has been growing controversy over
genetically modified foods. Unfortunately, it can be difficult to find
independent, scientifically rigorous information about this hotly
debated topic. As nurses, our patients, families, and friends look to
us for information regarding a variety of health matters, including
nutrition; yet many of us have not been formally educated about
nutrition. By educating ourselves about this important subject, we can
become advocates for our communities and ourselves in regards to
genetically modified foods.

Genetically modified foods are described in the literature under a
variety of other names. These all refer to the same process. They
refer to the selection of desired traits from one organism and its
genetic placement into another organism. Theoretically, genetically
modified foods have the potential to be very beneficial. For example,
traits that make plants resistant to harmful insects can be inserted,
nutrients that were not previously in that particular plant may be
added, or modifications can be made to improve the ability of a plant
to grow in regions of the world where the conditions are inhospitable
to the growth of traditional, non-modified plant varieties.
Genetically modified foods have been increasingly used by farmers and
were grown on over 109 million acres in 2001 and over half of the soy
grown worldwide has been genetically engineered. So why is there so
much controversy surrounding genetically modified foods? In order to
understand the differing views one should first know how genetically
modified foods are made.

The method of genetically modifying foods is a highly technical
process. In order to produce the desired trait, many different genes,
from a variety of organisms, need to be inserted. Many genetically
modified foods have over 30 added genes. First the gene that produces
the desired trait is isolated. This gene is then spliced into bacteria
that are known to attach to seeds and transmit genes into them. The
bacteria is mixed with the seeds that the scientist would like
modified and if all goes as planned the bacteria transmits the gene to
the seed. It is not enough that the gene is transmitted but the gene
must be inserted in the right place on the seed DNA for the trait to
be produced.

Scientists have developed a system to easily determine if the gene is
in the correct position. They add a gene that causes resistance to a
particular antibiotic. After the genes have been transmitted, they
expose the seeds to this antibiotic. If the inserted genes are in the
correct place, the antibiotic will not kill the seeds. These resistant
seeds are then selected and grown. The plants grown from these seeds
will then be tested for the desired trait.


The many names of genetically modified foods:

** Transgenic

** Genetically engineered

** Bioengineered

** Genetically modified organisms


The use of antibiotic resistant traits in genetic modification has
been one of the sources of controversy and raises a red flag for
nurses. There is concern that these traits could be transferred to the
humans and animals that eat these foods, exacerbating an already
widespread problem of antibiotic resistance. This could negatively
impact the ability of nurses to provide quality care for our patients.
Nurses are painfully aware of the limited armament we have to combat
infections and recognize the threat that antibiotic resistant
organisms could present.

In a study that addresses safety concerns such as changes in
nutrients, toxins, and allergens, the National Academy of Sciences
(NAS) has recently released guidelines for implementing safety
assessments of genetically modified foods (Safety of Genetically
Engineered Foods: Approaches to Assessing Unintended Health Effects,
2004). Current mandates require companies to assess for "intended and
predictable" effects of genetic modification. The NAS is recommending
these mandates be changed to a more thorough safety assessment that
includes unexpected changes. They also recommend that genetically
modified organisms be evaluated after market introduction in order to
monitor the real life experience and validate the initial safety
assessment. This tracking system would be especially useful in
identifying allergens within genetically modified foods and
determining the prevalence of allergic reactions to these foods within
the general population.

One of the marketing ploys most frequently sited by the companies that
create genetically engineered seeds is that these seeds may have the
ability to reduce the impact of important global diseases. For
example, Vitamin A deficiency is common in developing countries
worldwide. This deficiency is the most common cause of childhood
blindness and is implicated in the deaths of many malnourished
children and adults. Even though supplementation is inexpensive and
easy to provide, many developing countries do not have the resources
to distribute it. Scientists have developed a type of rice that
produces beta-carotene (which the body converts to Vitamin A). The
ability to produce beta-carotene was taken from a daffodil gene. This
gene makes the rice turn a yellow color and the rice has thus been
called "Golden Rice."

On the surface "Golden Rice" sounds like an amazing advancement, but
as you delve deeper, some yellow flags emerge. First, beta-carotene
must be converted into Vitamin A. It is estimated that only 10% of
beta-carotene is actually made into Vitamin A. When using this
estimate, a child would have to eat approximately six pounds of cooked
Golden Rice each day in order to get the recommended daily allowance
of Vitamin A. Also, some fat in the diet is required to adequately
absorb beta-carotene. Many malnourished people do not have sufficient
fat in their diet, thereby impeding their ability to absorb beta-
carotene. Golden Rice is still not available for use by the public so
its ability to reduce Vitamin A deficiency remains to be seen.

Another marketing strategy of the genetically modified seed industry
is its claim that genetically modified crops will increase worldwide
production of food, thereby reducing world hunger. They extend this
argument to claim that if larger quantities of food are produced on
existing farmland, the world's growing population will be able to be
fed without further destruction of rainforests and other
environmentally sensitive areas. This supposition does not address the
true causes of hunger in most of the world. As stated by the American
Dietetic Association, "There is sufficient food to feed
everyone...Poverty, gender inequity, ethnocentrism, racism, and lack
political will are all key constraints to solving the problem of world
hunger and malnutrition" (Struble & Aomari, 2003). Hunger is not
caused by a lack of food being produced, but rather an inability to
pay for food and social and political unrest that make it difficult to
obtain, distribute and/or grow food. Also, most of the genetically
engineered crops being developed are not varieties that can be grown
in climates where malnutrition is most prevalent. The varieties being
developed are those that will have the ability to make the most
profit, such as corn and soybeans, which are key elements in the
processed foods that are likely to be consumed in developed countries,
like the United States.

Another argument of the industry is that genetically modified plants
may reduce the amount of agricultural pesticides used. Pesticides can
have a significant, negative health effect on the farmers who use
them, the consumers who ingest pesticide residues on the foods they
consume, and the whole ecosystem. As genetically modified crops have
become more prevalent, a reduction in pesticide use is not always
found. In fact, in some areas of the United States, pesticide use has
actually increased. This may be due to the difficulty in growing these
crops in certain areas of the country. Also, some crops have been
engineered to be resistant to herbicides (a type of pesticide). With
this resistance, farmers can now spray more herbicides, such as weed
killers, without having to worry about the chemicals affecting their
crop, thus increasing the amount of pesticides used.

One way that decreased pesticide use may be achieved is by the
addition of a gene from the bacteria Bacillus thurengiensis (Bt). This
causes plants to produce a substance that is toxic to insects. Organic
farmers have used Bt for years as a natural insecticide.
Unfortunately, insect pests are very good at becoming resistant to
insecticides. The widespread use of genetically modified Bt crops has
made many in the organic farming community concerned that one of the
few resources they have available to combat insect pests may soon be
ineffective. Bt is also used in many communities to control the
mosquito population. With the increasing number of mosquito-born
illnesses, such as the West Nile virus, it is vital that the
effectiveness of this important form of mosquito control be
maintained. Finally, there is evidence that Bt enhanced crops may
negatively affect monarch butterfly populations (Losey et al, 1999).
While there are conflicting studies regarding this outcome, it seems
likely that monarch butterflies have the potential to be seriously
harmed by Bt containing plants. Are there other vulnerable populations
- animal, insect, human -- that could also be affected? The science is
not yet developed to answer this question.

Nurses consistently support full disclosure labeling policies on the
basis that people have the right to know and make informed decisions
about what they eat, drink, and breathe. However, corporations have,
to date, successfully lobbied against labeling genetically modified
foods. They state that these foods have been deemed safe by the
federal government so no additional labeling is required. Still,
consumers have consistently asked for labeling of genetically modified
foods. As the acclaimed food and nutrition author and professor at New
York University Marion Nestle states, "If we are what we eat and we
don't know what we are eating, do we know who we are?" There is the
potential for allergic reactions and labeling would allow people with
known allergies to make informed food choices. Individuals who do not
eat meat may object to eating products that have animal genes added.
Without labeling they are unable to know if what they are eating goes
against their religious or moral beliefs.

The issues regarding genetically modified foods are complex It may be
that a cautious approach is the best one. In 2003, the American Nurses
Association adopted the Precautionary Principle as its guiding tenet
for environmental health. This principle advocates a cautious approach
to technologies that have the potential to cause negative
environmental or health effects. Though there are many potential
benefits from genetically modified foods, the possibility of far-
reaching negative outcomes should direct us towards a more thorough
study of these foods before their widespread use. Such an approach
would place us on a safer, more precautionary path.


Committee on Identifying and Assessing Unintended Effects of
Genetically Engineered Foods on Human Health, National Research
Council. (2004). Safety of Genetically Engineered Foods: Approaches to
Assessing Unintended Health Effects. The National Academies Press:
Washington, D.C.

Losey, J.E., Rayor, L.S., &Carter, M.E. (1999). Transgenic pollen
harms monarch larvae. Nature, 399, 214.

Struble, M.B. & Aomari, L.L. (2003). Addressing world hunger,
malnutrition and food insecurity. Retrieved September 15, 2004 from
American Dietetic Association web site