Processed Meats vs. Beets: Does the Source of Nitrates or Nitrites Matter?
- allygallop
- May 26
- 8 min read
Avoid nitrates added to deli meats and bacon because they cause cancer, yet promote plant sources of nitrates to improve exercise efficiency and cardiovascular health?
Both scenarios are true, but given how sports dietitians promote dietary and supplemental nitrate intakes for athletic performance, we should understand the full picture.
In this article I’m going to review:
What are nitrates, nitrites, and nitric oxide? How much do we need?
Nitrate conversion to nitric oxide.
Where nitrates and nitrites are located in the food system.
Are there health risks associated with nitrates and nitrites, and do these change if from plants or processed, cured meats?
Nitrates, Nitrites, and Nitric Oxide: What Are They and How Much Do We Need?
The nitrate molecule is one nitrogen bound to three oxygen molecules, simplifying to two oxygens for nitrite and then one oxygen for nitric oxide (NO). Nitrates and nitrites work through two separate pathways that produce the desirable endpoint of NO.
The importance of NO relates to the cardiovascular system. A reduction in NO has been linked with hypertension, obesity, reduced insulin sensitivity, and cardiovascular disease, in part due to the role of NO in vasodilation and endothelial health. (1-2) Regarding exercise, it’s the NO production linked with oxygen efficiency, but the impact is greater in those who are not highly trained, partaking in endurance-type sports, and potentially has a greater effect in men than women. (3-5)
The nitrate dose for endurance performance regarding oxygen efficiency is ~370-500 mg nitrates consumed ~2-3 hours prior to exercise. This equates to ~500 mL 100% beet juice or ~70 mL for a concentrated beet shot. (4) Skeletal muscles may also act as a reservoir for nitrates, allowing for a local source of nitrates for when NO is needed in the muscle for contractile, metabolic, and vascular processes. (4,6)
However, the acceptable daily intake (ADI) for nitrates and nitrites is based off one’s body weight:
Nitrates are 0-3.7 mg/kg/day.
Nitrites are 0-0.07 mg/kg/day. (7)
For a 150-lb. adult (68 kg), the ADIs would be 252 mg for nitrates and 4.8 mg for nitrites—far less nitrates than what’s used in sport. This is another example of exercise research differing from public health recommendations (read my caffeine article here). In consulting with a scientist when researching this topic, they mentioned disagreeing with the low nitrate ADIs.
How are Nitrates Converted in the Body?
Speaking of pathways, when something like NO is vital, it’s smart to have multiple ways to produce it. Thus, there are two known pathways for how the body makes NO:
The L-arginine-NO pathway.
The nitrate-nitrite-NO pathway.
The L-arginine-NO pathway
This pathway occurs in the endothelial tissue, or the cells lining our blood vessels. (8) L-citrulline is converted to L-arginine, which in turn uses the enzyme nitric oxide synthase to produce NO. (4)
Yet as we get older, this pathway is neither as efficient nor reliable in producing NO, which makes dietary sources of nitrates that much more important. (9) Hence, the next pathway.
The nitrate-nitrite-NO pathway
This pathway is also called the enterosalivary circulation pathway.
Step 1 – The mouth: Nitrite is formed from nitrate with the help of bacteria located on the back third of the tongue. (9-10) The nitrites are then swallowed. (10)
Step 2 – The stomach: Nitrite interacts with stomach acid to form nitrous oxide and then NO. (10)
Note that the pathway is entirely reversible and nitrates—regardless of their dietary source—can form nitrites within the body. Both nitrates and nitrites are precursors and sources for NO. Nitrates can be absorbed in the intestine and sent to the mouth to be stored in the salivary glands (~25% of ingested nitrates are found here), secreted into the saliva to be used in the pathway once again. (2,4,8)
Given the requirement of bacterial action within this pathway, bacterial mouthwash is of concern. Kapil et al. (2013) had study participants hold antiseptic mouthwash in their mouths for five minutes, twice daily, for a week. The researchers discovered that this “nearly abolished oral conversion of nitrate to nitrite … accompanied by a decrease in plasma nitrite concentration (~25%) and a concomitant increase in blood pressure.” (11)
Nitrates and Nitrites in the Food System
Nitrogen-rich fertilizers are used on farms to help plants grow and maximize crop yields. When the plant absorbs the nitrogen, it’s converted to nitrates. This is a main reason why ~50-85% of our daily nitrate intake comes from vegetables, and the remainder mainly from drinking water, especially in well water. (7,9,12)
The World Health Organization estimated the daily nitrite intake at 1.2-3.0 mg. (8) The main sources of dietary nitrites are cured and processed meats (e.g., bacon, bologna, hot dogs, lunchmeat, canned meat, sausages, smoked fish). (12-13) Both sodium nitrite and/or sodium nitrate are added to meats, the latter of which are converted to nitrites. (14) Some meats may advertise being free of added nitrites or nitrates because they replace sodium nitrite or nitrate with celery salt, celery juice, spinach extract, or beetroot extract. (8)
Nitrites serve both experiential and food safety roles:
Provides color and taste.
Prevents the growth of the deadly bacteria Clostridium botulinum. (12)
Not quite food, but tobacco contains tobacco-specific nitrosamines (or TSNAs). TSNAs are well known carcinogens found in tobacco and its smoke. (15)
The Risks of Nitrate and Nitrite Intake: Processed and Cured Meats
Nitrate molecules on their own are inert: it’s only once they’re transformed can they be either health promoting or concerning. (12)
The main concern with processed and cured meats is the development of N-nitroso compounds, like nitrosamines, which aren’t added to foods as an ingredient, but are formed when in the presence of other ingredients and precursors. (16) Nitrosamines are produced in the presence of high heat (cooking), acid (stomach acid), amides, and/or amines*. (8) When you take a cured meat like bacon and cook it, you get nitrosamines—meaning frying bacon is one of the highest sources of nitrosamine production. (13) The concern for nitrosamines is when they interact with DNA, increasing one’s risk of various cancers. (7)
Thus, in 2015 the International Agency for Research on Cancer (IARC) categorized processed meats as a Group 1 carcinogen due to its contributing role in colorectal and stomach cancers. (17)
Keep in mind that so long as the ingredients for nitrosamine production exist in the gastrointestinal tract, nitrosamines can be formed. (8)
*Amines contain carbon-nitrogen bonds whereas amides contain nitrogen connected to a carbonyl group (carbon double bound to oxygen). These are found in protein/meat, so they provide a substrate for nitrosamine production. (18)
Meat versus Plant: The Nitrate Nuance
Of note, the nitrates in beets and those added to meats are identical, as are the nitrites. (19) Nitrates and nitrites on their own are not carcinogenic. (8) Whether you eat bacon or not, are an omnivore or a vegan, you will still have nitrite and nitrosamine production occurring in the body, but the lower the dietary intake of processed and cured meats, the lower your intake and internal production will be.
Although humans can produce nitrosamines from vegetable sources of nitrates, data shows a protective effect of nitrates from vegetables compared to an increased relative risk of gastric cancer risk with nitrite and nitrosamine consumption. In plants, the presence of antioxidants reduces the number of nitrosamines being formed. Vitamin C, carotenoids, and polyphenols, for instance, can speed up the conversion to NO, thereby reducing nitrite concentrations and their potential of nitrosamine formation, and help protect NO from reactive species to help prolong the half-life of NO. (7-8)
Ultimately, beyond nitrate and nitrite consumption, we have to consider the entire food: Vegetables contain fiber and health-promoting nutrients like antioxidants (which reduce nitrosamine formation and inflammation), potassium (for cardiovascular health), and fibre (for cardiovascular and immune health), whereas processed meats contain saturated fat and sodium. So even though the nitrates are identical, their vehicle is not. (19)
Key Takeaways
Avoid antibacterial mouthwash to maximize NO-producing pathways.
Avoid or minimize your intake of cured and processed meats.
Optimize your intake of vegetables high in nitrates, plus those high in polyphenols, vitamin A, and vitamin C to reduce your nitrosamine formation, to prioritize NO formation, and to protect NO.
References
(1) Koch, C.D., Gladwin, M.T., Freeman, B.A., Lundberg, J.O., Weitzberg, E., & Morris, A. (2017). Enterosalivary nitrate metabolism and the microbiome: intersection of microbial metabolism, nitric oxide and diet in cardiac and pulmonary vascular health. Free Radic Biol Med,105:48-67. https://pubmed.ncbi.nlm.nih.gov/27989792/
(2) Webb, A.J. (2024). “Every beet you take”: lowering systolic blood pressure and improving vascular function/exercise capacity via the dietary nitrate-nitrite-NO pathway in patients with COPD. Eur Respir J,63(2):2302238. https://pubmed.ncbi.nlm.nih.gov/38302179/
(3) Jones, A.M. (2014). Influence of dietary nitrate on the physiological determinants of exercise performance: a critical review. Appl Physiol Nutr Metab,39(9):1019-1028. https://pubmed.ncbi.nlm.nih.gov/25068792/
(4) Jeukendrup, A., & Gleeson, M. (2024). Sport Nutrition, fourth edition. Human Kinetics.
(5) de Zevallos, J.O., Hogwood, A.C., Kruse, K., De Guzman, J., Buckley, M., … & Allen, J.D. (2023). Sex differences in the effects of inorganic nitrate supplementation on exercise economy and endurance capacity in healthy young adults. J Appl Physiol,135(5):1157-1166. https://pubmed.ncbi.nlm.nih.gov/37823208/
(6) Piknova, B., Schechter, A.N., Park, J.W., Vanhatalo, A., & Jones, A.M. (2022). Skeletal muscle nitrate as a regulators of systemic nitric oxide homeostasis. Exerc Sport Sci Rev,50(1):2-13. https://pubmed.ncbi.nlm.nih.gov/34669624/
(7) Luetic, S., Knezovic, Z., Jurcic, K., Perasovic, M.L., & Sutlovic, D. (2025). Nitrates and nitrites in leafy vegetables: the influence of culinary processing on concentration levels and possible impact on health. Int J Mol Sci,26(7):3018. https://pubmed.ncbi.nlm.nih.gov/40243642/
(8) Karwowska, M., & Kononiuk, A. (2020). Nitrates/nitrites in food—risk for nitrosative stress and benefits. Antioxidants,9(241):241. https://pubmed.ncbi.nlm.nih.gov/32188080/
(9) Torregrossa, A.C., Aranke, M., & Bryan, N.S. (2011). Nitric oxide and geriatrics: implications in diagnostics and treatment of the elderly. J Geriatr Cardiol,8(4):230-42. https://pmc.ncbi.nlm.nih.gov/articles/PMC3390088/
(10) Lidder, S., & Webb, A.J. (2012). Vascular effects of dietary nitrate (as found in green leafy vegetables and beetroot) via the nitrate-nitrite-nitric oxide pathway. Br J Clin Pharmacol,75(3):677-96. https://pubmed.ncbi.nlm.nih.gov/22882425/
(11) Kapil, V., Haydar, S.M.A., Pearl, V., Lundberg, J.O., Weitzberg, E., & Ahluwalia, A. (2013). Physiological role for nitrate-reducing oral bacteria in blood pressure control. Free Radic Biol Med,55:93-100. https://pubmed.ncbi.nlm.nih.gov/23183324/
(12) Lanford, J. (2014, November). CPE monthly: dietary influences on lung cancer — here’s an evaluation of the research and strategies to help counsel patients. Today’s Dietitian. https://www.todaysdietitian.com/newarchives/111114p48.shtml
(13) United States Department of Agriculture. (2014). Cancer risk from nitrosamines in pork bacon. https://www.fsis.usda.gov/sites/default/files/media_file/2020-07/nitrosamine-risk-assessment.pdf
(14) The use of nitrates and nitrites in meat curing. (2016, February 6). The Explorations of a Gastrochemist. Retrieved May 26, 2025, from https://gastrochemist.com/nitrates/
(15) Fernández-Alba, A.m & Agüera, A. (2005). Nitrosamines. https://www.researchgate.net/publication/288159404_NITROSAMINES
(16) National Toxicology Program. 15th Report on Carcinogens [Internet]. Research Triangle Park (NC): National Toxicology Program; 2021 Dec 21. N-Nitrosamines: 15 Listings. Available from: https://www.ncbi.nlm.nih.gov/books/NBK590783/
(17) International Agency for Research on Cancer, World Health Organization. (2015). IARC monographs evaluate consumption of red meat and processed meat. https://www.iarc.who.int/wp-content/uploads/2018/07/pr240_E.pdf
(18) 20.5: Amines and amides. (n.d.). LibreTexts Chemistry. Retrieved May 26, 2025, from https://chem.libretexts.org/Bookshelves/General_Chemistry/Chemistry_1e_(OpenSTAX)/20%3A_Organic_Chemistry/20.05%3A_Amines_and_Amides
(19) Kamal, P. (2025, May 16). Are nitrates from beetroot and processed meats the same thing? Examine. https://examine.com/faq/are-nitrates-from-beetroot-and-processed-meats-the-same-thing/
