TY - JOUR
T1 - Ingestion of nitrate and nitrite and risk of stomach and other digestive system cancers in the iowa women’s health study
AU - Buller, Ian D.
AU - Patel, Deven M.
AU - Weyer, Peter J.
AU - Prizment, Anna
AU - Jones, Rena R.
AU - Ward, Mary H.
N1 - Publisher Copyright:
© 2021 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2021/7/1
Y1 - 2021/7/1
N2 - Nitrate and nitrite are precursors in the endogenous formation of N-nitroso compounds (NOC) which are potent animal carcinogens for the organs of the digestive system. We evaluated dietary intakes of nitrate and nitrite, as well as nitrate ingestion from drinking water (public drinking water supplies (PWS)), in relation to the incidence (1986–2014) of cancers of the esophagus (n = 36), stomach (n = 84), small intestine (n = 32), liver (n = 31), gallbladder (n = 66), and bile duct (n = 58) in the Iowa Women’s Health Study (42,000 women aged from 50 to 75 in 1986). Dietary nitrate and nitrite were estimated using a food frequency questionnaire and a database of nitrate and nitrite levels in foods. Historical nitrate measurements from PWS were linked to the enrollment address by duration. We used Cox regression to compute hazard ratios (HR) and 95% confidence intervals (CI) for exposure quartiles (Q), tertiles (T), or medians, depending on the number of cancer cases. In adjusted models, nitrite intake from processed meats was associated with an increased risk of stomach cancer (HRQ4vsQ1 = 2.2, CI: 1.2–4.3). A high intake of total dietary nitrite was inversely associated with gallbladder cancer (HRQ4vsQ1 = 0.3, CI: 0.1–0.96), driven by an inverse association with plant sources of nitrite (HRQ4vsQ1 = 0.3, CI: 0.1–0.9). Additionally, small intestine cancer was inversely associated with a high intake of animal nitrite (HRT3vsT1 = 0.2, CI: 0.1–0.7). There were no other dietary associations. Nitrate concentrations in PWS (average, years ≥ 1/2 the maximum contaminant level) were not associated with cancer incidence. Our findings for stomach cancer are consistent with prior dietary studies, and we are the first to evaluate nitrate and nitrite ingestion for certain gastrointestinal cancers.
AB - Nitrate and nitrite are precursors in the endogenous formation of N-nitroso compounds (NOC) which are potent animal carcinogens for the organs of the digestive system. We evaluated dietary intakes of nitrate and nitrite, as well as nitrate ingestion from drinking water (public drinking water supplies (PWS)), in relation to the incidence (1986–2014) of cancers of the esophagus (n = 36), stomach (n = 84), small intestine (n = 32), liver (n = 31), gallbladder (n = 66), and bile duct (n = 58) in the Iowa Women’s Health Study (42,000 women aged from 50 to 75 in 1986). Dietary nitrate and nitrite were estimated using a food frequency questionnaire and a database of nitrate and nitrite levels in foods. Historical nitrate measurements from PWS were linked to the enrollment address by duration. We used Cox regression to compute hazard ratios (HR) and 95% confidence intervals (CI) for exposure quartiles (Q), tertiles (T), or medians, depending on the number of cancer cases. In adjusted models, nitrite intake from processed meats was associated with an increased risk of stomach cancer (HRQ4vsQ1 = 2.2, CI: 1.2–4.3). A high intake of total dietary nitrite was inversely associated with gallbladder cancer (HRQ4vsQ1 = 0.3, CI: 0.1–0.96), driven by an inverse association with plant sources of nitrite (HRQ4vsQ1 = 0.3, CI: 0.1–0.9). Additionally, small intestine cancer was inversely associated with a high intake of animal nitrite (HRT3vsT1 = 0.2, CI: 0.1–0.7). There were no other dietary associations. Nitrate concentrations in PWS (average, years ≥ 1/2 the maximum contaminant level) were not associated with cancer incidence. Our findings for stomach cancer are consistent with prior dietary studies, and we are the first to evaluate nitrate and nitrite ingestion for certain gastrointestinal cancers.
KW - Diet
KW - Disinfection by-products
KW - Drinking water contaminants
KW - Esophagus cancer
KW - Gallbladder cancer
KW - Liver cancer
KW - Nitrate
KW - Nitrite
KW - Small intestine cancer
KW - Stomach cancer
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UR - http://www.scopus.com/inward/citedby.url?scp=85108423187&partnerID=8YFLogxK
U2 - 10.3390/ijerph18136822
DO - 10.3390/ijerph18136822
M3 - Article
C2 - 34202037
AN - SCOPUS:85108423187
SN - 1661-7827
VL - 18
JO - International journal of environmental research and public health
JF - International journal of environmental research and public health
IS - 13
M1 - 6822
ER -