Prospective study of dietary changes in cancer survivors for five years including pre- and post- diagnosis compared with those in cancer-free participants

Abstract

The number of long-term survivors after a cancer diagnosis is increasing. Few investigations have compared survivors’ diets to their original pre-diagnosis dietary pattern or with the patterns of cancer-free controls. We examined the dietary changes in survivors for five years (i.e. before to after diagnosis) in cancer survivors, comparing them with cancer-free controls in a prospective cohort study in Japan. Using 1995–1998 for the baseline and 2000–2003 for the follow-up survey, a validated food frequency questionnaire was administered to 33,643 men and 39,549 women aged 45–74 years. During the follow-up period, 886 men and 646 women had developed cancer. Participants that had not been diagnosed with cancer served as controls. There was a greater decrease in the calorie intake (median change: − 168 kcal/d [Interquartile range: − 640, 278]) in male cancer survivors compared to controls (− 33 kcal/d [− 453, 380], P