additives are underdiagnosed because they are not
often suspected; most maintain, however, that hyper-
sensitivity to food additives involves at most 1% of the
adult population and perhaps 2% of children.
Consumers who are concerned about a specific
artificial preservative in their food can check for its
presence by reading the labels of processed foods,
which are required by law to state the ingredients in
order by weight from the greatest amount to the least.
Those who wish to cut down on their intake of pres-
ervatives in general can try growing some of their own
produce, or purchase fresh fruits and vegetables only
from local farmers during the growing season.
EATING OUT.Some hypersensitivity reactions to
food preservatives occur in relation to food eaten at
restaurants. Restaurant foods are most likely to be the
culprit when the person has a reaction to a specific dish
served in a restaurant but not to that same food when
made at home. People who already know that they are
sensitive to sulfites may need to ask about specific
dishes at a restaurant ahead of time to inquire whether
they are made from foods containing high levels of
sulfites.
People allergic to high levels of sulfites should
avoid anything containing or garnished with bottled
(non-frozen) lemon or lime juice, wine, molasses,
grape juices, pickled cocktail onions, dried potatoes,
wine vinegar, gravies or sauces, Maraschino cherries,
fruit toppings, and sauerkraut. People who are sensi-
tive to moderate or low levels of sulfites should also
avoid fresh mushrooms, canned clams, avocado dip or
guacamole, pickles and relishes, maple syrup, corn
syrup, fresh shrimp, apple cider, and cider vinegar.
MEDICATIONS.People who suspect that they
are sensitive to artificial preservatives in eye drops
can ask their doctor or pharmacist for a formula
made without preservatives. Asthma inhalers that do
not contain sulfites are available for asthmatics with
sulfite allergies.
Interactions
No negative interactions between food preserva-
tives and prescription medications have been reported.
Some researchers in dentistry, however, are testing the
hypothesis that benzoates interact positively withflu-
orideby reinforcing the effects of fluoride in prevent-
ing dental cavities.
Aftercare
Hypersensitivity to food preservatives is usually
tested by a food challenge. The patient is given a diet
free of the suspected additive for a week or two and
then given foods containing the additive to see
whether the symptoms previously reported by the
patient recur. If they do, the advice of physicians and
researchers in the field is to simply avoid foods or
other products containing that preservative.
Testing for sulfite allergy should be done only by a
physician who has been trained in this procedure and
has some experience in using it. The test involves
administering increasing amounts of sulfites by
mouth to the patient while the doctor monitors the
patient’s lung function and other vital signs (blood
pressure, pulse rate, etc.) A sudden and significant
drop in lung function indicates that the patient is
sensitive to sulfites.Complications
There are no known complications to testing peo-
ple for hypersensitivity to artificial preservatives in
foods or to treating such hypersensitivity by avoiding
the additive in question.Parental concerns
Allergies
In general, food preservatives are no more likely to
cause allergic reactions in children than either coloring
agents or flavoring agents, which are the other major
categories of food additives. Some people develop
hives, itching, or nasal congestion when exposed to
one particular type of yellow food coloring, FD&C 5,
known as tartrazine. Monosodium glutamate (MSG), a
food additive sold under the trade name of Accent, is
also added to soups, broths, and some restaurant dishes
to intensify the flavors already present in the food.
Although MSG was reported to cause headaches, dry
mouth, and asthma attacks in some people—a group of
symptoms referred to as ‘‘Chinese restaurant syn-
drome’’ since the late 1960s, recent double-blind studies
indicate that there is no causal connection between
MSG and the reported symptoms.
The food preservatives most likely to cause aller-
gic reactions are the sulfites and the benzoates. Prior
to 1986, sulfites were commonly added to fresh pro-
duce in supermarkets and on restaurant salad bars to
prevent browning. Reports of sensitivity reactions,
however, led the FDA to ban the use of sulfites on
fresh produce, especially lettuce put out on salad bars.
As of 2007, the FDA requires all foods containing
more than 10 ppm of sulfites to declare sulfites on
the label. Foods containing less than 10 ppm of sulfites
have not been shown to cause allergic symptoms even
in people who are hypersensitive to sulfites.Artificial preservatives