January 4, 2011
by Betsey Booren, Ph.D
Nitrites. Preservatives. Additives. Media reports too often cite these words as if they’re something to fear rather than safe, beneficial food ingredients. So what is nitrite? And why do meat processors add it to some products?
As processors are well aware, nitrite is an ingredient added to make cured meats, including hot dogs and some sausages. In centuries past, before refrigeration, meat was salted to preserve it. Early sausage-makers recognized that using certain salts produced a distinct pink color and smoky flavor in meat products. In the 1800s, scientists came to understand that the salts contained nitrate, which became nitrite when added to meat. Not only did curing create a unique taste and color, it also delayed spoilage – a critical benefit before refrigeration. While refrigeration is common today, many consumers continue to enjoy the distinct taste and flavor of cured meats.Nitrite sources
While many consumers believe most nitrite consumed comes from cured meats, research shows that less than 5 percent of nitrite intake comes from cured meats. The vast majority comes from vegetables and our own saliva. Nitrate found in leafy green and root vegetables like spinach, beets, celery and lettuce is converted to nitrite when it comes into contact with human saliva. When it is swallowed, the nitrate becomes nitric oxide – an essential and critical compound used by the body to keep blood pressure levels normal, fight infection and support the nervous system.
People who hear the word botulism often think it’s a disease of the past. When it comes to cured meats, it certainly is. Why? Since nitrite has been added routinely to commercially cured meat products, not one case of botulism has been linked to these products.
In addition to preventing botulism, preserving shelf-life and adding color and flavor, meat scientists now understand that nitrite in cured meats is also extremely effective in reducing other bacteria than can still pose a problem, like the germ that causes the foodborne illness Listeriosis
.Nitrite safety and health benefits
The total body of scientific evidence clearly demonstrates that processed meats cured with nitrite are not only safe at the levels consumed, but nitrite actually offers health benefits. Consider the following:
• In 2000, the US National Toxicology Program completed a multiyear bioassay in which rats and mice were fed very high levels of nitrite – far higher than any human would ordinarily consume. A scientific panel determined that nitrite was not a carcinogen and voted to keep it off the list included in the Annual Report on Carcinogens.
• Ongoing research, including studies from the Univ. of Texas Health Science Center at Houston, indicates that nitrite can prevent injury from a heart attack, control blood pressure, promote wound healing, help treat sickle-cell anemia, prevent preeclampsia in pregnant women and may even prevent disease progression.
• New research suggests nitrite can inhibit cancer-cell progression at low doses during the early stages of colon cancer-cell development, according to a 2010 study by the Univ. of Texas and Michigan State Univ.
• The National Institutes of Health’s National Heart, Lung and Blood Institute is also researching nitrite’s health benefits. Mark Gladwin, MD, whose lab uncovered nitrite’s value as a medical treatment for various circulatory conditions, told reporters in September 2005, “The idea it’s bad for you has not played out…We think we stumbled into an innate protection mechanism.” Mythbusting for consumers
Consumers shouldn’t fear nitrite – the medical community certainly doesn’t anymore. Through sound science, nitrite’s safety and public-health benefits have been proven and consumers who understand the most-current facts surrounding nitrite will appreciate its value. Meat and poultry cured with nitrite, such as hot dogs and some sausages, should continue to be eaten without fear as part of a safe, healthy and balanced diet. Betsy Booren, Ph.D. is director of scientific affairs for the American Meat Institute Foundation