that varies with the wood used in the fire. Meats smoked over an open fire are exposed to
carcinogenic chemicals in the smoke, including a-benzopyrene. Meats treated with artifi-
cial smoke flavoring are not, since the flavoring is commercially treated to remove tar and
a-benzopyrene. Cured and smoked meats sometimes have less moisture and proportionally
more fat than fresh meat. They are also saltier. Aging—letting the meat hang exposed to
air—further reduces the moisture content and shrinks the meat.
Irradiation. Irradiation makes meat safer by exposing it to gamma rays, high-energy ion-
izing radiation, the kind of radiation that kills living cells including potentially hazardous
microorganisms. The process does not change the way meat looks, feels, or tastes, nor does
it make the food radioactive. But it does change the structure of some naturally occurring
chemicals in meat, breaking molecules apart to form new compounds called “radiolytic
products” (abbreviated as RP). About 90 percent of these compounds are also found in non-
irradiated foods. The rest, called “unique radiolytic products” (URP), are found only in irradi-
ated foods (including meat). In 1985, the Food and Drug Administration approved the use of
low doses of radiation to kill Trichinella spiralis, the organism in pork that causes trichinosis.
Today, irradiation is an approved technique in more than 37 countries around the world,
including the United States. NOTE: Irradiation reduces the amount of thiamin (vitamin B 1 )
in pork. (See above, Preparing this food.)
Medical Uses and/or Benefits
Adverse Effects Associated with This Food
Trichinosis. Trichinosis comes from eating improperly cooked meat contaminated with
cysts of Trichinella spiralis, a parasitic roundworm found in meat-eating animals. Meat-fed
hogs are not the only source of trichinosis; Arctic explorers have gotten trichinosis from
polar bear meat. About 10 to 100 cases of trichinosis from pork are reported each year in the
United States; many mild cases, with symptoms similar to those of a mild flu, undoubtedly
remain undiagnosed. See What happens when you cook this food, above.
Increased risk of cardiovascular disease. Like other foods from animals, pork is a source of
cholesterol and saturated fats, which increase the amount of cholesterol circulating in your
blood and raise your risk of heart disease. To reduce the risk of heart disease, the National
Cholesterol Education Project recommends following the Step I and Step II diets.
The Step I diet provides no more than 30 percent of total daily calories from fat, no
more than 10 percent of total daily calories from saturated fat, and no more than 300 mg
of cholesterol per day. It is designed for healthy people whose cholesterol is in the range of
200–239 mg/dL.
The Step II diet provides 25–35 percent of total calories from fat, less than 7 percent
of total calories from saturated fat, up to 10 percent of total calories from polyunsaturated
fat, up to 20 percent of total calories from monounsaturated fat, and less than 300 mg
Pork