Consumption of large amounts of both whole and refined grains raises mortality risk among breast cancer patients

Increased intake of whole grains may worsen the adverse associations of refined grains with mortality in breast cancer survivors, the study stated. 

USA: A new study published in the journal Nutrients suggests that the existing recommendations for breast cancer survivors' dietary consumption of whole grains need to be reviewed.

Due to cancer therapy, breast cancer patients may have a decreased ability to digest whole grains. This study, by Deepali Karina Ernest and colleagues, looked at the separate and combined effects of whole grain and refined grain diets on overall mortality among breast cancer survivors.

3081 female breast cancer survivors participated in the study and gave demographic, nutritional, and lifestyle information at baseline, year 1, and year 4. The National Death Index (NDI) and death certificates were used to corroborate the semi-annual telephone interviews' assessments of mortality. Using Cox proportional hazards models, the relationships between whole grain and refined grain and the incidence of fatalities were examined.

The key findings of this study were:

1. While higher intake of whole grains was not substantially linked with death due to breast cancer, it was somewhat associated with an increased risk of total mortality.

2. Consuming more refined grains was linked to a higher risk of overall and breast cancer-specific death. Researchers also looked at the interactions between whole grain and refined grain and overall mortality.

3. Among individuals who consumed a lot of refined grains, those who also consumed a lot of whole grains had a greater risk of dying from all causes than those who did not.

4. The negative relationships between refined grains and mortality among breast cancer survivors may be made worse by increased whole grain consumption.

In conclusion, current dietary recommendations for cancer patients call for a high intake of whole grains (about 3-6 servings per day), but they do not address refined grain consumption. However, even more startlingly, consuming large amounts of both whole and refined grains may raise mortality risk by 52% when compared to consuming large amounts of whole grains just.

Reference: 

Ernest, D. K., Lemus, H., Hsu, F.-C., Pierce, J. P., & Wu, T. (2022). The Independent and Joint Associations of Whole Grain and Refined Grain with Total Mortality among Breast Cancer Survivors: A Prospective Cohort Study. In Nutrients (Vol. 14, Issue 16, p. 3333). MDPI AG. https://doi.org/10.3390/nu14163333