Table 1.

Characteristics of study participants by sex-specific quintiles of intake of dietary flavonoids in the NIH–AARP Diet and Health Study (1995–1996)

Sex-specific quintile of intake
Q1Q2Q3Q4Q5
No. males58,65058,64958,65058,64958,649
No. females39,71939,71939,71839,71939,718
Age at entry, median (IQR), year62 (57–66)63 (58–67)63 (58–67)63 (58, 67)63 (58–67)
Race/ethnicity (%)
 White, non-Hispanic9191919191
 Black, non-Hispanic44443
 Hispanic22221
 Asian, Pacific Islander, Native American11123
Education (%)
 Less than high school2924242525
 High school graduate10991010
 Some college2423232323
 College graduate3340413939
Body mass index (%)
 <25 kg/m23436353335
 25–29.9 kg/m24141424242
 30–34.9 kg/m21615151615
 ≥35 kg/m276666
Cigarette smoking status (%)
 Never3034373837
 Former4851504948
 Current181191011
Family history of cancer (%)
 No4646464647
 Yes4949494848
Alcohol intake, median (IQR), g/d1.4 (0.0–11.7)2.6 (0.2–15.4)2.3 (0.2–13.1)1.8 (0.2–9.8)1.5 (0.2–7.8)
Tea consumption, >1 cup/d, %39266191
Total caloric intake, median (IQR), kcal/d1,794 (1,339–2,380)1,736 (1,321–2,269)1,667 (1,276–2,175)1,709 (1,282–2,253)1,561 (1,189–2,024)
Intakes of flavonoids-rich foods, median (IQR)
 Orange and tangelos, cups/d/1,000 cal0.03 (0.01–0.07)0.07 (0.03–0.20)0.07 (0.03–0.32)0.07 (0.03–0.35)0.07 (0.03–0.20)
 Orange and grape fruit juice, cups/d/1,000 cal0.04 (0.01–0.16)0.17 (0.04–0.41)0.27 (0.05–0.56)0.26 (0.05–0.58)0.19 (0.04–0.50)
 Legume, cups/d/1,000 cal0.05 (0.02–0.12)0.06 (0.03–0.14)0.06 (0.03–0.14)0.06 (0.03–0.13)0.05 (0.02–0.10)
 Grape, servings/d/1,000 cal0.02 (0.01–0.05)0.02 (0.01–0.05)0.02 (0.01–0.13)0.02 (0.01–0.13)0.02 (0.01–0.05)
 Banana, servings/d/1,000 cal0.03 (0.00–0.15)0.05 (0.00–0.20)0.05 (0.00–0.32)0.05 (0.00–0.21)0.05 (0.00–0.15)

NOTE: Percentages did not add up to 100% because of missing (<5%).