The study, “Effect of mistimed eating patterns on breast and prostate cancer risk (MCC‐Spain Study),” appeared in the International Journal of Cancer.
Disruption of the body’s internal clock, or circadian rhythm, has been associated with diseases such as cancer, obesity, and type 2 diabetes. Working nights has been linked to prostate and breast cancer, although not all studies support this correlation.
Experimental studies have shown that changes in meal timing affect inflammation, glucose levels, and cancer growth. However, unlike the type and the quantity of food intake, less evidence has been published about the relationship between cancer and the timing of eating. Data on the influence of diet and other factors on prostate cancer risk is particularly limited.
To assess if the timing of eating and sleep patterns are associated with prostate and breast cancer risk, the research team conducted a large population-based study. They also evaluated whether the timing of meals alters the effect of factors associated with cancer risk, such as adherence to cancer prevention recommendations, age, educational level, body mass index, family history of cancer, and smoking status.
The research included 621 patients with prostate cancer and 1,205 with breast cancer who were assessed from 2008 to 2013. A total of 2,193 controls (of which 1,321 were women) were also included. Information about the timing of meals and sleep was collected via face-to-face interviews, while dietary habits were reported with a food frequency questionnaire that included 140 food items.
The results showed that compared to participants sleeping immediately after dinner, those who went to bed two or more hours after eating had a 20 percent reduction in prostate and breast cancer.
The data also showed that having dinner before 9 p.m. led to similar benefits when compared to eating after 10 p.m.
Scientists also found that a longer dinner-sleep interval was more effective in people who followed cancer prevention recommendations and who preferred morning, rather than evening, activities.
“Adherence to diurnal eating patterns and specifically a long interval between last meal and sleep are associated with a lower cancer risk, stressing the importance of evaluating timing in studies on diet and cancer,” the researchers wrote.
“If the findings are confirmed, they will have implications for cancer prevention recommendations that currently do not take meal timing into account,” Manolis Kogevinas, the study’s lead author, said in a press release. “The impact could be especially important in cultures such as those of southern Europe where people tend to have supper late.”