Intake and food sources of nitrites and N-nitrosodimethylamine in Spain.
OBJECTIVE
To conduct a comprehensive assessment of dietary intakes of nitrites and N-nitrosodimethylamine (NDMA).


METHODS
A study was conducted within the Spanish cohort of the European Prospective Investigation in Cancer and Nutrition (EPIC) to assess the intake and food sources of these compounds in Spanish adults. The study included 41,446 health volunteers, aged 29-69 years, from Northern and Southern regions. Usual food intake was estimated by in-person interviews using a computerised dietary questionnaire.


RESULTS
The estimated geometric mean was 0.994 mg day(-1) for nitrites and 0.114 microg day(-1) for NDMA. For both compounds a positive trend in consumption with increasing energy intake was observed. Dietary NDMA was related to age and sex after energy adjustment, while nitrite consumption increased with higher intakes of vitamin C (P < 0.001). The food groups that contributed most to intakes were meat products, cereals, vegetables and fruits for nitrites, and processed meat, beer, cheese and broiled fish for NDMA. Current and past smokers, who had high levels of NDMA from tobacco exposure, were also identified as the highest consumers of dietary NDMA. Furthermore, smokers had low intakes of vitamin C (an inhibitor of endogenous nitrosation).


CONCLUSIONS
Intake levels of NDMA and nitrites in a Mediterranean cohort are currently relatively lower than those previously reported, although processed meat, beer and cured cheese still are the most important contributors to NDMA intake.
Jakszyn
Paula
P
Institut Català d'Oncologia (ICO-IDIBELL), L'Hospitalet de Llobregat, 08907 Barcelona, Spain. paujak@iconcologia.catsalut.net
Agudo
Antonio
A
Berenguer
Antonio
A
Ibáñez
Raquel
R
Amiano
Pilar
P
Pera
Guillem
G
Ardanaz
Eva
E
Barricarte
Aurelio
A
Chirlaque
María Dolores
MD
Dorronsoro
Miren
M
Larrañaga
Nerea
N
Martinez
Carmen
C
Navarro
Carmen
C
Quirós
José R
JR
Sanchéz
María José
MJ
Tormo
María José
MJ
González
Carlos A
CA
D000328:Adult; D017677:Age Distribution; D000368:Aged; D000818:Animals; D002611:Cheese / Q000009:adverse effects / Q000032:analysis; D015331:Cohort Studies; D004032:Diet; D004034:Diet Surveys; D002149:Energy Intake; D005260:Female; D005504:Food Analysis; D005511:Food Handling / Q000379:methods; D006801:Humans; D008297:Male; D008460:Meat / Q000009:adverse effects / Q000032:analysis; D008875:Middle Aged; D009573:Nitrites / Q000008:administration & dosage* / Q000032:analysis*; D009602:Nitrosamines / Q000008:administration & dosage* / Q000032:analysis*; D011446:Prospective Studies; D017678:Sex Distribution; D012907:Smoking; D013030:Spain; D011795:Surveys and Questionnaires
D009573:Nitrites; D009602:Nitrosamines; C025033:N-amyl-N-methylnitrosamine