Table 1

Baseline characteristics according to BMF at baseline for 487 198 participants

More than once a dayOnce a dayOnce every 2 to 3 daysLess than three times a week
Number of participants, n (%)46 426
(9.5)
373 054
(76.6)
46 570
(9.6)
21 148
(4.3)
Women, %45.957.772.682.5
Age, year53.051.550.651.0
Urban area, %33.343.943.749.4
Middle school and above, %46.749.549.148.4
Agricultural and industrial workers, %58.257.457.957.5
Household income ≥20 000 RMB/year, %41.843.440.638.8
Married, %91.491.090.289.2
Current tobacco smoker, %
 Men68.267.570.472.5
 Women2.62.72.83.2
Current daily alcohol drinker, %
 Men25.421.015.314.8
 Women1.01.00.80.7
Physical activity, MET-hours/day22.021.621.320.9
Regular consumption of*, %
 Red meat47.047.446.945.3
 Fresh vegetables98.598.298.598.2
 Fresh fruits27.228.126.723.5
Body mass index, kg/m2 24.523.622.822.6
Waist circumference, cm82.480.277.977.3
Hypertension, %38.834.227.525.7
Diabetes, %6.05.25.56.4
Kidney disease†, %1.91.41.31.4
COPD†, %8.56.97.07.7
Family history of, %
 Cancer18.016.416.617.2
 Diabetes8.36.76.76.8
 Heart attack3.63.13.13.6
 Stroke19.417.517.017.2
  • Baseline characteristics were presented as mean or percentage. Age and sex were not adjusted, and others were adjusted for age, sex and survey sites as appropriate. Linear trend was assessed by assigning consecutive integers to four BMF categories in a separate model. All p values for trend were <0.001, except for agricultural and industrial workers (p=0.359), regular consumption of fresh vegetables (p=0.955), the prevalence of diabetes (p=0.024), family history of cancer (p=0.010) and heart attack (p=0.486).

  • *Regular consumption was defined as consumption at least 4 to 6 days per week.

  • †Participants with kidney disease or COPD were further excluded from the analyses of the corresponding outcome.

  • BMF, bowel movement frequency; COPD, chronic obstructive pulmonary disease; MET, metabolic equivalent of task.