The preservative sodium nitrite fights harmful bacteria in ham, salami and other processed and cured meats and also lends them their pink coloration. However, under certain conditions in the human body, nitrite can damage cells and also morph into molecules that cause cancer.
Still, if you wanted to avoid this preservative, you would have to cut out more than just ham to go cold turkey on nitrite. In a typical person’s diet, 80 percent of nitrite comes from vegetables such as spinach, radishes and lettuce, and another 13 percent comes from swallowed saliva.
In massive doses, nitrate which changes to nitrite in the body can lead to a condition called methemoglobinemia. Most common in infants, this condition occurs when nitrite in the blood deactivates hemoglobin, which allows red blood cells to carry oxygen. Nitrate contamination of drinking water, which can occur when nitrate fertilizer makes its way into a well, is a frequent cause.
If all goes well in the body, nitrite in the diet transforms in the gut into nitric oxide, which serves a variety of important functions in the body
Under certain conditions, nitrite can instead form nitrosamines, molecules that cause cancer in lab animals.
However, the food that accompanies nitrate and nitrite into the gut helps determine how the molecules act once they get there. Meat manufacturers now add the antioxidant ascorbic acid, or vitamin C, to their products, which promotes the formation of relatively harmless nitric oxide and counteracts the development of the possibly cancer-causing nitrosamines.
Evidence is mounting that nitrite preservatives are safe, but that doesn’t mean processed meats are healthy.
Gotten from: livescience.com