Encyclopedia of Diets - A Guide to Health and Nutrition

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condition or have a longer period of freshness. In
1994, the first bioengineered food to be introduced to
the consumer market in the United States was the
Flavr Savr tomato. This tomato was bioengineered
to ripen more slowly and to remain on the vine longer
so that it would be available to consumers later in the
year than other tomatoes.
Bioengineering can also be used to increase the
nutrient content of foods, or to addvitaminsthat are
not usually found in a certain food. A variety of rice,
sometimes referred to as ‘‘golden rice,’’ that includes
beta-carotene has been developed. Beta-carotene is a
provitamin tovitamin A, which means that the body
can use it to produce vitamin A. Rice is a staple of the
diet of many Asians, and because rice does not nor-
mally contain vitamin A, many people in Asia are
vitamin A deficient. This deficiency is believed to
have resulted in blindness in a quarter of a million
children in southeast Asia alone. If the new strain of
rice that contains beta-carotene is introduced to the
area, it could help to eliminate vitamin A deficiency
and significantly reduce childhood blindness.

Description
All people have deoxyribonucleic acid (DNA) in
their cells. DNA is where all of the information needed
to produce and sustain life is stored. DNA is made up
of strands of nucleic acids that are grouped to form
individual genes. Each gene contains the information
about how to synthesize a particular protein. The
proteins synthesized lead to individual characteristics,
such as hair and eye color in humans.
Plants also contain DNA, as do almost all other
living things. When scientists genetically engineer a
plant, they take a gene from another plant or organism
such as a bacterium and insert it into the original plant
or trade it for a gene in the original plant. This trading
of genes is called transposing.
Scientists did not learn how to insert and trans-
pose genes successful until the 1980s. However, long
before this people had been trying to create better,
heartier plants and animals through selective breed-
ing. For hundreds of years farmers had selected and
bred animals based on characterizes that they wanted
the offspring to have. Farmers might decide to breed a
cow that gave a higher quantity of milk than other
cows in the hopes of producing more cows that gave an
above average quantity of milk. Farmers also planted
the seeds of plants that had desirable characteristics
hoping to produce more plants with those same traits.
Although many people were engaged in trying to
make new, better, plants and animals for many years it

was not until the work of Gregor Mendel in the nine-
teenth century that people began to be understood how
traits were passed from one generation to the next. He
did research on pea plants and discovered that traits
were passed from one generation to the next in a way
that could be predicated. Peas had a much simpler
inheritance pattern than most organisms, so even with
this knowledge it was very difficult for scientists to
produce plants with the exact traits they wanted. Plants
with the desired trait had to be cross bred, and then
plants from the resulting generation that had the
desired traits had to be selected and cross bred again
and again. It takes many generations of plants to pro-
duce offspring that regularly have the desired trait.
Today, scientists do not have to cross breed plants
repeatedly to get a new variety of plant that has the
traits or characteristics they desire. Instead, they
search for a gene in another plant that will produce
the desired characteristics and insert it into the DNA
of the original plant. Often two or three different genes
are inserted, sometimes each from different plants or
animals. Plants that have had this done are considered
bioengineered. It is estimated that more than 50% of
the soybeans grown in the United States, and more
than 25% of the corn have been bioengineered in some
way. About two-thirds of processed foods contain
some form of bioengineered crop.
Bioengineered foods are regulated and monitored
by three different government agencies: the United
States Food and Drug Administration (FDA) the
United States Department of Agriculture (USDA)
and the Environmental Protection Agency (EPA).
The FDA is responsible for the regulation and labeling
of the bioengineered foods, the USDA oversees the
safety and completeness of test fields used by bioen-
gineering companies to test their new plants, and the
EPA regulates any bioengineered plants that contain
pesticide-related genes.
Before companies can put a genetically engineered
food on the market they need to prove that it is safe for
consumers. The FDA requires that companies prove
that the bioengineered food is just as safe and nutritious
as the non-bioengineered equivalent. This includes pro-
viding information for the FDA to review about the
kinds of proteins synthesized by the new gene or genes,
nutritional content, toxicology reports, and other infor-
mation. Labeling of bioengineered foods is voluntary,
and is left to the discretion of the company.

Precautions

There is a small chance that some people might
have an unexpected allergic reaction to proteins

Bioengineered foods

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