• Hot dogs contain preservatives called nitrites.hot dog image by dinostock from Fotolia.com
  
  Many Americans eat processed food full of preservatives, often from a box. Food producers use preservatives to prevent bacteria from growing and prolong a product's shelf life. Preservatives can also slow the ripening of fruits and vegetables so they last longer. Common preservatives include nitrites for cured meat, sulfites to prevent discoloration and benzoates used in some beverages.
  
  

Nitrites

• Preservatives called nitrites found in cured meats including sausage, bacon and hot dogs may increase the risk of lung disease, according to a scientists from Columbia University. A 2006 study linked regular consumption of cured meats to a 71 percent higher risk of chronic obstructive pulmonary disease (COPD). The disease, which causes excessive mucus production in the lungs, has no cure and can cause death. The study found an increased risk of the disease among people who ate meat treated with nitrites 14 times each month. Nitrites prolong the life of meat and also make it pink. Doctors have traditionally linked COPD to smokers, but Columbia assistant professor R. Graham Barr said that 10 percent of people who die from the disease have never smoked.
  
  

Sulfites

• Sulfites are used to prevent discoloration on shrimp and dried fruits, as well as keep wine bacteria-free as it ferments. Sulfites can cause breathing problems for people with sulfite sensitivities -- about 1 percent of the population, according to the Food and Drug Administration. Asthmatics, about 5 percent of the general population, can also experience breathing problems after ingesting sulfites. Although the FDA says that most people can eat sulfites without a problem, it has issued regulations to protect people with sulfite sensitivities. Restaurants can't put sulfites on food in salad bars, and food manufacturers must list the substance on labels. Symptoms of a reaction can resemble an asthma attack. The FDA cautions asthmatics to bring their inhalers if they go out to eat.
  
  

Sodium Benzoate

• According to the Center for Science in the Public Interest, people can safely ingest the preservative sodium benzoate except when used in combination with ascorbic acid, also known as Vitamin C. In an acidic substance, the two chemicals can mix and form benzene, which the center links to cancers such as leukemia. The risk is small, but the center says people shouldn't be exposed to any risk. Sodium benzoate is commonly used in fruit juices, salad dressings, jams and pickles. The Food and Drug Administration has recommended that food and beverage manufacturers refrain from using sodium benzoate in conjunction with ascorbic acid, but hasn't banned the combination. Some soft drink manufacturers have stopped using sodium benzoate, however.