The Environmental Working Group (EWG) released its first ever “Dirty Dozen Food Additives” list today, no doubt looking to build upon its “Dirty Dozen” produce guide. While the produce guide is at least based on USDA data (though applied in a flawed manner), the new list seems to be only based on EWG perceptions, not established science. The inclusion of nitrates and nitrites at the top of the list is a perfect example of those perceptions. Nitrite’s safety was questioned in the 1970s but since then research shows it is not only not carcinogenic, it may have health benefits.
The U.S. National Toxicology Program (NTP), which is considered the “gold standard” in determining whether substances cause cancer, completed a multi-year study in which rats and mice were fed high levels of sodium nitrite. The study found that nitrite was not associated with cancer. NTP maintains a list of chemicals found to be carcinogenic. Sodium nitrite is not on that list. EWG cites the NTP for other compounds on its list but conveniently ignores the NTP findings on nitrite. We have to guess that’s because the findings do not fit the EWG narrative.
Sources of Nitrite
The EWG also ignores the fact that cured meats are not a major source of nitrite in our bodies. Less than five percent of daily nitrite intake comes from cured meats. Nearly 93 percent of nitrite comes from leafy vegetables, tubers and our own saliva. Vegetables contain nitrate, which is converted to nitrite when it comes into contact with saliva in the mouth. In fact, the amount of nitrate in some vegetables can be very high. Spinach, for example, may contain 500 to 1900 parts per million (ppm) of nitrate; radishes may contain 1500 to 1800 ppm and lettuce may contain 600 to 1700 ppm. The nitrate to nitrite conversion process from eating vegetables makes up 85 percent of the average human dietary nitrite intake. By contrast, the amount of nitrite allowed by USDA to be added to cured meats is miniscule at no more than 156 ppm. In most cases, the amount added is 120 ppm or less and after processing the amount remaining in the final product is typically 10 ppm or less. This amount is approximately one-fifth the level of 25 years ago.
Health Benefits of Nitrite
But what EWG fails to communicate is the critically important role nitrites and nitrates have on in the human body. Our own bodies have a healthy nitrogen cycle, which recycles nitrites and nitrates to nitric oxide. You are asking what is nitric oxide and why is it important? Called the “Molecule of the Year” by Science Magazine in 1992, nitric oxide is an amazing chemical that the body uses to control blood pressure, kill tumor cells and heal wounds. When nitrite oxide is done with its work, its byproduct is nitrite. So clearly, nitrite is something that is made by the body as part of its normal, healthy processes.
In fact evidence is mounting that nitrite actually does have numerous health benefits. The body converts nitrate to nitrite to nitric oxide to regulate blood pressure, promote wound healing, destroy pathogens in the gut and even to prevent preeclampsia during pregnancy. Scientists at the National Institutes of Health (NIH) over the last several years have announced a number of studies that document the health benefits of nitrite. These scientists have concluded that nitrite is a potential new treatment for organ transplantation, heart attacks, sickle cell disease, and leg vascular problems.
Dr. Mark Gladwin of NIH’s National Heart, Lung and Blood Institute, whose lab uncovered nitrite’s value as a medical treatment, 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.” Gladwin said NIH believes so strongly in its promise that it is seeking a pharmaceutical company to help develop it as a therapy.
This is all research the EWG once again ignored. Perhaps if they want to take a deeper look at the science on nitrite, they’ll include it on a new list of “12 Additives that May Benefit Your Health.” Until then, we recommend they do some more research before putting out such misleading materials.