Characteristics of the study participants according to the presence or absence of a family history of colorectal cancera
| No family history n = 81,802 | Family history n = 6,956 | |
|---|---|---|
| Age (yr) | 46.7 | 46.8 |
| Body mass index (kg/m2) | 24.3 | 24.3 |
| Alcohol intake (g/day) | 6.6 | 6.8 |
| Dietary intakeb | ||
| Folate (μg/day)c | 365 | 365 |
| Methionine (g/day) | 1.9 | 1.9 |
| Animal fat (g/day) | 52.2 | 51.9 |
| Dietary fiber (g/day) | 16.8 | 16.9 |
| Beef, pork or lamb as a main dish (servings/week) | 2.6 | 2.6 |
| Calcium (mg/day)c | 732 | 732 |
| Vitamin D (IU/day)c | 292 | 291 |
| Regular aspirin use (%)d | 23.5 | 26.4 |
| Multivitamin supplement use (%) | 34.0 | 34.1 |
| Mean duration of multivitamin use at baseline (yr)e | 4.4 | 4.3 |
| Mean duration of multivitamin use in 1994 (yr)f | 8.0 | 8.1 |
| Screening endoscopy use at baseline (%) | 5.4 | 5.7 |
| Screening endoscopy use through study follow-up (%)g | 20.3 | 43.1 |
| Regular vigorous exercise (%)b | 44.7 | 46.0 |
| Mean pack-years of smoking before age 30 yr | 3.0 | 2.9 |
a Based on reports of a family history of colorectal cancer in one or more first-degree relatives obtained at study initiation. Values are means directly standardized according to the age distribution of the cohort.
b Dietary values represent the mean energy-adjusted intake.
c Includes the use of supplements.
d Defined as aspirin use on two or more days/week.
e Mean duration of use among multivitamin users at baseline.
f Mean duration of use among multivitamin users in 1994.
g Includes screening endoscopy use during study follow-up and at baseline.
hRegular vigorous exercise was defined as vigorous physical activity (enough to work up a sweat) on one or more days/week.