Are Nitrates Deadly?

Column #212

National Public Radio recently ran a commentary about consumers being duped by the meat industry. It said that deli meat processed with nitrates is carcinogenic and will cause cancer. The other beef it reported was that uncured meats with celery juice or celery powder have the same nitrate levels as conventional deli meats and therefore the meat industry is conning consumers.^1-3

Well, as with many media sources these days the gripes are partially true, partially false, and unequivocally another “the-sky-is-falling” report.¹⁴

Here are some actual facts.

USDA regulations state that meats cured with celery powder or celery juice must be called “uncured” in order to distinguish them from conventionally cured meats. A majority of meat industry professionals do not agree because meats cured with celery powder are no different from meats cured with nitrates. But meat processors must comply with USDA regulations. So if this is a con, then it’s the government’s nanny state that created it.⁴

Many years ago regular salt was used when storing meats in order to prevent spoilage. Today sodium nitrate (a salt) is used to cure meat. Curing meat this way is a significant food safety benefit because it prevents the growth of Clostridium botulinum, which causes botulism, one the deadliest foodborne illnesses.⁴

Nitrate (NO₃) and nitrite (NO₂) do not cause cancer. In fact nitrites have recognized health benefits. The human body makes nitrite as part of its normal, healthy nitrogen cycle. It’s in sea salt. It’s found naturally in most vegetables! Dietary nitrite helps regulate blood pressure, prevents brain damage following a stroke, promotes wound healing, and other positives.^5-8

Here is where the story gets muddled and cancer scares come to the forefront. Burned meats (and most burned foods) can be carcinogenic. High heat cooking is an unhealthy practice which is why meats, cured or fresh, should never be cooked with high temperatures. They should never be burned like we so often see with hot dogs and hamburger patties cooking over an open fire. Personally I don’t even sear meats in order to prevent burning and excessive dehydration. I want juicy meat.

The Food Safety Inspection Service of the USDA says this about “nitrosamines” which are carcinogenic.

Meats treated with nitrates are more susceptible to the dangers of high heat cooking. Under certain conditions, the products from the natural breakdown of proteins known as “amines” can combine with nitrites to form compounds known as “nitrosamines.” There are many different types of nitrosamines, most of which are known carcinogens in test animals.

Not all cured meat products contain nitrosamines; however, when present, they usually are in very minute amounts. Many variables influence nitrosamine levels: amount of nitrite added during processing, concentrations of amines in meat, type and amounts of other ingredients used in processing, actual processing conditions, length of storage, storage temperatures, method of cooking, and degree of doneness.

A bacon cooking study, “Effect of Frying and Other Cooking Conditions on Nitrosopyrrolidine Formation in Bacon” (Journal of Science, Vol. 39, pages 314-316), showed no evidence of nitrosamines in bacon fried at 210°F for 10 minutes (raw), 210°F for 15 minutes (medium well), 275°F for 10 minutes (very light), or 275°F for 30 minutes (medium well). But when bacon was fried at 350°F for 6 minutes (medium well), 400°F for 4 minutes (medium well), or 400°F for 10 minutes (burned), some nitrosamines were found. Thus, well-done or burned bacon is potentially more hazardous than less well-done bacon. Also, bacon cooked by a microwave has less nitrosamine than fried bacon.¹⁰

Studies on humans regarding whether or not meats with nitrates are causing higher cancer levels are difficult to conduct. They are based on asking people what they ate over many years which is highly unreliable. Studies on rats, where diets can be regimented for the life of the animal, are more reliable. But in most rat studies the quantities fed per body mass may greatly exceed what any consumer could eat. So conclusions are based on theories rather than fact. For instance, in the United Kingdom it’s “estimated” that six out of 100 people will get bowel cancer in their lives. Of those who eat two ounces of processed meat daily, their chances become seven out of 100.¹¹

To prevent bacteria growth and also the possible conversion of nitrates into nitrosamines, nitrate levels in cured meats have specific maximum levels. Many years ago the U.S. Department of Agriculture set a limit of 200 parts of sodium nitrite preservatives per million parts of meat, by weight. The level of sodium nitrate cannot contain more than 500 parts per million.^{12, 13}

Far and away the largest source of nitrates in our diet comes from fresh vegetables. In fact their nitrate levels are so high many are not safe foods for infants. It’s highly recommended that home-prepared infant foods from vegetables (such as spinach, beets, green beans, squash, carrots) should be avoided until infants are three months or older.⁹

Overall nitrates are safe when meats are cooked responsibly. So, please load up my cauliflower pizza with grass-fed cheese and pepperoni. But don’t burn my pizza.

To your health.

Ted Slanker

Ted Slanker has been reporting on the fundamentals of nutritional research in publications, television and radio appearances, and at conferences since 1999. He condenses complex studies into the basics required for health and well-being. His eBook, The Real Diet of Man, is available online.

Don’t miss these links for additional reading:

1. Duped In The Deli Aisle? ‘No Nitrates Added’ Labels Are Often Misleading by Allison Aubrey from NPR.org

2. Danger at the Deli by Trisha Calvo from Consumer Reports

3. Petition to Require Accurate and Non-Misleading Labeling on Meat Processed with Non-Synthetic Nitrates and Nitrites from USDA FSIS Docket Clerk

4. Myth: The Use Of Celery Powder To Cure Some Meats Is Misleading from Meat Mythcrushers

5. Myth: Nitrite In Cured Meat Is Linked To Diseases Like Cancer from Meat Mythcrushers

6. Are Nitrates and Nitrites in Foods Harmful? by Kris Gunnars, BSc from healthline.com

7. Food Sources of Nitrates and Nitrites: The Physiologic Context for Potential Health Benefits by Norman G Hord, et al.

8. Nitrate and Nitrite in Health and Disease by Linsha Ma, et al.

9. Nitrates and Homemade Baby Food – Learn about Nitrates in Carrots etc.

10. Bacon and Food Safety from USDA Food Safety and Inspection Service

11. The Truth about Nitrates in Your food by Angela Dowden from BBC