Preservatives are chemical ingredients added to processed foods to prevent growth of bacteria and mold, delay spoiling and make the product appear more appealing to consumers. However, the use of food preservatives may increase your risk for respiratory, immunologic and other metabolic complications. Review the food labels of each product you consider consuming to determine what, if any, preservatives it contains.
Antimicrobial Preservatives
Antimicrobial preservatives, such as benzoates, sorbates, propionates and nitrites, inhibit growth of bacteria and mold on foods. Sodium benzoate and potassium benzoate inhibit growth of microorganisms in acidic foods with a pH below 3.6 and 4.5, respectively, such as vinegar, salad dressings, fruit juices, carbonated beverages, soy sauce and duck sauce. Sodium sorbate, potassium sorbate and calcium sorbate prevent growth of yeasts, mold and fungi in foods and beverages with a pH below 6.5, such as yogurt, cheese and baked products. Some people may experience skin rashes or itching from sorbates. Sodium propionate, potassium propionate and calcium propionate prevent growth of mold that do not require an acidic environment, particularly baked goods like breads and cakes. Sodium nitrite is used in smoked fish and meats to give the products more appealing pink or red color and to inhibit growth of bacteria, including the Clostridium botulinum bacteria that causes botulism, a deadly disease. Nitrites are toxic and convert to nitrosamines in your stomach. Nitrosamines are carcinogenic substances that may increase your risk of developing cancer, including stomach cancer and nasopharyngeal cancer, according to research by Susanna Larsson published in the "International Journal of Cancer" in 2006 and Mary Ward published in the "International Journal of Cancer" in 2000.
Antioxidants
Sulfites, butylated hydroxyanisole (BHA), and butylated hydroxytoluene (BHT) prevent oils and fatty foods from decomposing. Sodium sulfite, sodium bisulfite, sodium metabisulfite, potassium bisulfite, and potassium metabisulfite inhibit growth of yeast and fungi, prevent discoloration and are used in beer, wine, fruit juices and dried fruit. Sulfites may produce severe respiratory reactions, including difficulty breathing, asthma and death in people who are hypersensitive to the preservative. BHA prevents oxidation in vegetable oils, butter, lard, nuts, potato chips, snack foods, baked goods, meats and desserts. BHT is used in oils, fats and shortenings to prevent spoilage. BHA and BHT may have carcinogenic properties, but research by Anita Botterweck published in "Food and Chemical Toxicology" in 2000 did not find a significant association with intake of low levels of BHA and BHT and risk of stomach cancer.
Chelating Agents
Polyphosphates, citric acid and disodium ethylenediaminetetraacetic acid (EDTA) bind and prevent metal ions from oxidizing and spoiling foods. EDTA is added to soft drinks that contain sodium benzoate to prevent the formation of benzene, a carcinogenic substance. Exposure to benzene increases the risk for breast cancer, according to research by Adele Costantini published in "Tumori" in 2009. The agent polyphosphates prevent discoloration in fruits and vegetables. Citric acid adds flavor and extends the shelf life of foods.
References
- Diet Health: Artificial Preservatives
- Science Daily: Focusing on Preservatives: How They Keep Food Fresh
- "International Journal of Cancer"; Processed Meat Consumption, Dietary Nitrosamines and Stomach Cancer Risk in a Cohort of Swedish Women; Larsson, S.C.; Aug 15 2006
- "International Journal of Cancer"; Dietary Exposure to Nitrite and Nitrosamines and Risk of Nasopharyngeal Carcinoma in Taiwan; Ward, M.H.; June 1 2000
- Cleveland Clinic: Sulfite Sensitivity
