Table 4.

Joint effects of adult exercise and sport activity levels, occupational activity levels, energy intake, and BMI on breast cancer risk

Energy intake (kcal/d)
BMI (kg/m2)
Low (<21)Intermediate (21 ≤ BMI ≤ 25)High (≥25)
All women
    Adult exercise/sports (MET-h/d/y)
        YesLow (<1,794)1.0 (Reference)0.94 (0.52-1.71)0.92 (0.48-1.76)
High (>1,794)0.74 (0.37-1.46)0.91 (0.51-1.63)0.81 (0.44-1.50)
        NoLow (<1,794)1.12 (0.66-1.90)1.25 (0.75-2.09)1.69 (0.98-2.89)
High (>1,794)0.93 (0.54-1.60)1.47 (0.88-2.46)1.79 (1.06-3.05)
        Pinteraction0.65
Premenopausal
    Occupational activity (h/d/y)
        YesLow (<1,794)1.0 (Reference)1.12 (0.83-1.52)1.08 (0.72-1.61)
High (>1,794)0.85 (0.59-1.21)1.23 (0.90-1.68)1.22 (0.85-1.75)
        NoLow (<1,794)1.57 (0.88-2.79)1.48 (0.88-2.51)2.82 (1.29-6.18)
High (>1,794)1.30 (0.64-2.65)1.99 (1.13-3.53)1.51 (0.64-3.54)
        Pinteraction0.14
Postmenopausal
    Adult exercise/sports (MET-h/d/y)
        YesLow (<1,794)1.0 (Reference)0.90 (0.35-2.31)1.15 (0.45-2.77)
High (>1,794)0.59 (0.19-1.84)1.03 (0.43-2.51)1.12 (0.45-2.77)
        NoLow (<1,794)1.36 (0.55-3.40)1.59 (0.68-3.73)2.55 (1.07-6.04)
High (>1,794)1.01 (0.39-2.58)1.83 (0.79-4.25)2.84 (1.21-6.67)
        Pinteraction0.21
  • NOTE: Data were adjusted for age at interview, education, income, history of fibroadenoma, history of breast cancer among first-degree relatives, menopausal status, height, and ever had live birth. Occupational activity was measured as the average time spent in standing or walking and classified into one of three activity categories (i.e., heavy, medium, or nonphysical work).