Changes in diet, physical activity, and supplement use among adults diagnosed with cancer.

OBJECTIVE To investigate the prevalence and predictors of changes in diet, physical activity, and dietary supplement use among cancer patients. Design/subjects Telephone interviews of a population-based sample of 126 breast, 114 prostate, and 116 colorectal cancer patients from the state of Washington. ANALYSIS Logistic regression was used to estimate the odds ratio as a measure of the association of participant characteristics with lifestyle changes in the 12 months before the interview. RESULTS Overall, 66.3% of patients reported making lifestyle changes: 40.4% made one or more dietary changes, 20.8% added new physical activity, and 48.0% started taking new dietary supplements. Compared with men, women were 2.2 times more likely to take new dietary supplements (P <.01). Compared with patients aged 35 to 59, those aged 60 to 69 and 70 or older were statistically significantly less likely to make dietary changes (odds ratio = 0.39 and 0.54, respectively) or to take new supplements (odds ratio = 0.42 and 0.69, respectively). Compared with patients who received only one medical treatment, those receiving three or more treatments were more likely to make dietary changes (odds ratio = 2.6) or to start new physical activity (odds ratio = 3.0). Patients diagnosed 12 to 24 months before the interview were as likely to report making lifestyle changes as those diagnosed within one year of the interview. Having a stronger desire for personal control or internal locus of control predicted use of new dietary supplements (P for trend <.05 for both). Applications/conclusions Cancer survivors are likely to be making lifestyle changes and represent a group that could benefit from counseling on diet and physical activity.