Dietary nitrate and nitrite intake and risk of non-Hodgkin lymphoma

Abstract

Although established risk factors such as immunodeficiency and viral infections may be responsible for a portion of non-Hodgkin lymphoma (NHL) cases, the vast majority of NHL cases remain unexplained. The role of dietary nitrate and nitrite in NHL risk is of interest since they are precursors of N-nitroso compounds and nitrosoureas have been shown to induce B and T-cell lymphomas in animal studies. However, few studies have evaluated the potential association between consumption of nitrate and nitrite intake and NHL by subtype or chromosomal translocation status, and the results of these studies have been inconsistent. We estimated the dietary intake of nitrate and nitrite using a food frequency questionnaire in a population-based, case-control study of 348 cases and 470 controls conducted in Nebraska in 1999–2002. A non-significant excess risk of NHL was found among women who reported an intake of nitrite in the highest quartile compared to the lowest quartile (OR = 1.6; 95% CI: 0.8–2.9), particularly nitrite from animal sources (OR=1.9; 95% CI: 1.0–3.4). No significant associations were observed for nitrate or nitrite by NHL subtype. Although there were some increases in risk that support the N-nitroso hypothesis, they were not significant and do not confer strong evidence of an association.

Association between dietary nitrate and nitrite intake and site-specific cancer risk: evidence from observational studies

“…Limited number of studies available precluded any meaningful subgroup analyses for linear dose-response meta-analyses. Eighteen [ 6 , 9 , 15 , 22 , 23 , 34 , 35 , 42 , 43 , 45 , 46 , 48 , 50 , 52 – 54 , 61 , 62 ] and twelve [ 5 , 6 , 9 , 34 , 42 , 43 , 45 , 46 , 48 , 50 , 52 , 53 ] studies were included in the dose-response analysis for dietary nitrate and nitrite respectively. The summary RR for each increase by 10mg/day for dietary nitrate intake was 0.99 (95%CI = 0.98-1.00) with moderate to high heterogeneity (I2 = 63.4%).…”

The relationship between consumption of nitrite or nitrate and risk of non-Hodgkin lymphoma

“…In addition, two studies were identified from the reference lists of the retrieved and review articles. After reading the full texts, 8 case-control and 4 follow-up studies that reported the correlation between nitrate or nitrite consumption and risk of NHL published between 1996 and 2013 were selected [14][15][16][17][18][19][20][21][22][23][24][25] . Table 1 displays the fundamental characteristics of the articles included in the review.…”

“…During the past decades, the relationship between risk of NHL and nitrate or nitrite consumption have been investigated in several epidemiological publications, yet the results are contradictory. Some surveys failed to show positive or negative associations [14][15][16][17][18][19][20][21] , while others have revealed significant correlations [22][23][24][25] . When no specific trend can be ascertained from any individual investigation, combining a number of independent studies can reveal hidden associations through meta-analysis.…”

Red and Processed Meat Consumption Increases Risk for Non-Hodgkin Lymphoma

“… 13 , 16 Other potential mechanisms which might underlie an increased risk of NHL risk with red and processed meat consumption, involve NOCs, which have been linked to the risk of lymphoma in humans. 44 , 45 …”