December 22, 2022
2 min read
One author reports receiving funding from the French Pork Institute. The other authors report no relevant financial disclosures.
Dietary nitrates/nitrites from food additives were associated with greater risk for hypertension vs. naturally occurring nitrates/nitrites in food and water, researchers reported.
In addition, researchers observed no protective benefits of any nitrates/nitrites — natural or additive — on CVD risk, according to a study published in the Journal of the American Heart Association.
“We are commonly exposed to dietary nitrites and nitrates, through natural presence in vegetables, as well as water and soil contamination. Nitrites and nitrates are also widely used as food additives because of their preservative properties and the pink coloration they provide to some processed meats,” Bernard Srour, PharmD, PhD, nutritional epidemiology scientist and Nutritional Epidemiology Research Team member at Sorbonne Paris Nord University in Villetaneuse, France, and colleagues wrote.
“While a beneficial role of dietary nitrate in the cardiovascular function has been suggested in some interventional studies in healthy volunteers and patients and some observational studies, our results do not support any evidence for cardiovascular benefits of nitrites or nitrates,” the researchers wrote. “On the contrary, we observed for the first time, associations between additives-originated nitrites and a higher hypertension risk.”
This study included 106,288 adults from the French NutriNet-Santé cohort who participated in online questionnaires between 2009 and 2022, including a biannual series of nonconsecutive validated web-based 24-hour dietary records (median age at baseline, 41 years; 79% women). Using a food composition database, researchers estimated exposure to naturally occurring sources of nitrites/nitrates in food and water and exposure to nitrites/nitrates from additive sources including potassium nitrite, sodium nitrite, sodium nitrate and potassium nitrate.
Hypertension risk from nitrites/nitrates
During a median follow-up of 7.2 years, 3,810 cases of incident hypertension and 2,075 cases of CVD (MI, ACS, angioplasty, angina pectoris, stroke and transient ischemic attack) were reported via the questionnaire and verified using diagnostic support reports, hospital admissions and/or anatomic pathology reports.
Researchers reported that higher intake of additive-originated nitrites/nitrates was associated with greater risk for hypertension compared with naturally occurring sources of nitrites/nitrates (HR = 1.19; 95% CI, 1.08-1.32; P = .001), especially for consumers of sodium nitrite (HR = 1.19; 95% CI, 1.08-1.32; P = .002).
“The associations might be explained by the suggested role of nitrites in promoting oxidative damage in different organs,” the researchers wrote. “In addition, N-nitroso compounds (essentially formed during meat processing) have been shown to increase the risk of insulin resistance and coronary heart disease”
Nitrites/nitrates and CVD risk
Researchers also observed no association between intake of naturally occurring nitrites/nitrates and risk for incident hypertension (P > .3) and association between nitrites/nitrates from any source and risk for CVDs (P for all > .2).
“Although these findings need confirmation in other large-scale prospective and experimental studies in order to draw firm conclusions, they provide new evidence in the context of current discussions regarding the need for a reduction in the use of nitrite additives in processed meats by the food industry, as stated by the latest report of the French Agency for Food, Environmental and Occupational Health and Safety,” the researchers wrote. “Our results are in line with dietary guide-lines recommending that the population limit their consumption of processed meats as well as foods containing controversial additives, among which is sodium nitrite.”