Table 1.
Baseline characteristics in the Nurses Health Study study population by lowest and highest quintiles of heterocyclic amine (HCA) and meat derived mutagenic activity (MDM) intake
| PhIP (ng/day) | MeIQx (ng/day) | DiMeIQx (ng/day) | Meat derived mutagenic activity (revertant colonies/day) | |||||
|---|---|---|---|---|---|---|---|---|
| Q1 (14.3) | Q5 (201) | Q1 (3.4) | Q5 (39.1) | Q1 (0.27) | Q5 (5.5) | Q1 (834) | Q5 (7372) | |
| Mean age (yrs) | 64.7 | 61.3 | 63.4 | 62.8 | 64.0 | 62.3 | 64.2 | 62.1 |
| Mean pack years smoking among smokers | 24.0 | 25.9 | 22.1 | 29.0 | 22.9 | 27.6 | 23.5 | 26.8 |
| Mean age at first birth | 22.8 | 22.8 | 23.0 | 22.8 | 23.0 | 22.9 | 22.9 | 22.8 |
| Age at menarche <12 y (%) | 49.1 | 49.2 | 50.0 | 47.8 | 50.0 | 48.4 | 49.4 | 49.0 |
| Parity, >=3 children (%) | 58.5 | 61.8 | 57.5 | 62.7 | 57.1 | 62.7 | 58.6 | 61.1 |
| Height (inches) | 64.5 | 64.5 | 64.5 | 64.5 | 64.5 | 64.5 | 64.5 | 64.5 |
| BMI (kg/m2) | 25.7 | 27.1 | 25.3 | 27.4 | 25.5 | 27.2 | 25.5 | 27.1 |
| Physical activity (METs) | 18.8 | 18.3 | 20.9 | 15.9 | 20.1 | 17.0 | 19.2 | 17.8 |
| Family history of breast cancer in mother/sisters (%) | 14.8 | 14.2 | 15.1 | 14.0 | 15.0 | 14.4 | 15.0 | 14.4 |
| History of benign breast disease (%) | 31.4 | 30.7 | 33.2 | 29.3 | 32.7 | 29.0 | 32.1 | 30.1 |
| Mean daily intake † (94 FFQ) | ||||||||
| Calories (kcal) | 1602 | 1813 | 1526 | 1911 | 1541 | 1858 | 1557 | 1845 |
| Total fat (gm) | 48.4 | 62.0 | 42.4 | 71.5 | 44.0 | 67.0 | 46.3 | 64.4 |
| Total iron (mg) | 20.5 | 20.7 | 20.8 | 20.6 | 20.6 | 20.4 | 20.1 | 20.8 |
| Folate (mcg) | 488 | 485 | 505 | 466 | 501 | 472 | 486 | 483 |
| Alcohol (gm) | 3.8 | 6.1 | 4.2 | 5.4 | 4.2 | 5.5 | 4.3 | 5.3 |
| Processed meat (serv/day) | 0.07 | 0.10 | 0.04 | 0.14 | 0.05 | 0.12 | 0.06 | 0.11 |
| Chicken +turkey (serv/day) | 0.32 | 0.44 | 0.36 | 0.38 | 0.36 | 0.40 | 0.31 | 0.43 |
| Red meat (serv/day) | 0.11 | 0.18 | 0.05 | 0.27 | 0.06 | 0.24 | 0.08 | 0.21 |
Standardized for age in 1996 except for age and age at first birth; Q1 = lowest quintile, Q5 = highest quintile, number in parenthesis denote median value in each quintile (ng/day for heterocyclic amines and revertant colonies/day for meat derived mutagenic activity)
Mean daily intakes of nutrients are energy-adjusted
If not noted otherwise numbers denote mean values
Abbreviations:
MeIQx=2-amino-3,8-dimethylimidazo [4,5,-f] quinoxaline;
DiMeIQx=2-amino-3,4,8-trimethylimidazo [4,5,-f];
PhiP=2-amino-1-methyl-6-phenylimidazo [4,5-b] pyridine
BMI=Body mass index
MET=Metabolic equivalent hours per week