Dietary flavonoid intake and non-Hodgkin lymphoma risk.
BACKGROUND
The role of dietary factors in non-Hodgkin lymphoma (NHL) risk is not yet well understood. Dietary flavonoids are polyphenolic compounds proposed to be anticarcinogenic. Flavonoids are well-characterized antioxidants and metal chelators, and certain flavonoids exhibit antiproliferative and antiestrogenic effects.


OBJECTIVE
We aimed to evaluate the hypothesis that higher flavonoid intake is associated with lower NHL risk.


METHODS
During 1998-2000, we identified incident NHL cases aged 20-74 y from 4 US Surveillance, Epidemiology, and End Results cancer registries. Controls without history of NHL were selected by random-digit dialing or from Medicare files and frequency-matched to cases by age, center, race, and sex. Using 3 recently developed US Department of Agriculture nutrient-specific databases, flavonoid intake was estimated from participant responses to a 117-item food-frequency questionnaire (n = 466 cases and 390 controls). NHL risk in relation to flavonoid intake in quartiles was evaluated after adjustment for age, sex, registry, education, NHL family history, and energy intake.


RESULTS
Higher total flavonoid intake was significantly associated with lower risk of NHL (P for trend < 0.01): a 47% lower risk in the highest quartile of intake than in the lowest (95% CI: 31%, 73%). Higher intakes of flavonols, epicatechins, anthocyanidins, and proanthocyanidins were each significantly associated with decreased NHL risk. Similar patterns of risk were observed for the major NHL subtypes--diffuse large B-cell lymphoma (n = 167) and follicular lymphoma (n = 146).


CONCLUSIONS
A higher intake of flavonoids, dietary components with several putative anticarcinogenic activities, may be associated with lower NHL risk.
Frankenfeld
Cara L
CL
Division of Cancer, Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Rockville, MD 20852, USA.
Cerhan
James R
JR
Cozen
Wendy
W
Davis
Scott
S
Schenk
Maryjean
M
Morton
Lindsay M
LM
Hartge
Patricia
P
Ward
Mary H
MH
D000328:Adult; D000368:Aged; D000872:Anthocyanins / Q000008:administration & dosage; D016588:Anticarcinogenic Agents / Q000008:administration & dosage*; D000975:Antioxidants / Q000008:administration & dosage*; D002392:Catechin / Q000008:administration & dosage; D004032:Diet; D004034:Diet Surveys; D004305:Dose-Response Relationship, Drug; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage*; D044948:Flavonols / Q000008:administration & dosage; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance; D044945:Proanthocyanidins / Q000008:administration & dosage; D012042:Registries; D012307:Risk Factors; D018426:SEER Program; D014481:United States / Q000453:epidemiology
D000872:Anthocyanins; D016588:Anticarcinogenic Agents; D000975:Antioxidants; D005419:Flavonoids; D044948:Flavonols; D044945:Proanthocyanidins; C013221:proanthocyanidin; D002392:Catechin