The global mortality rate of breast cancer has decreased gradually due to effective treatment, with the 5-year survival rate now at 80 %. Therefore the quality of life (QOL) of breast cancer survivors is of increasing importance. Changes in diet and the use of supplements can be both beneficial and detrimental to breast cancer survivors’ quality of life. However, currently there is no comprehensive data documenting changes in dietary patterns and supplemement intake in a Chinese population of breast cancer survivors and the relationship with the change in their QOL.
This study aimed to explore and document changes in dietary intake of various food/food groups, nutrients and supplements before and after diagnosis in breast cancer patients and examine how they were associated with changes in QOL.
The study had two parts. Part 1 was a focus group discussion to explore attitudes and opinions towards the possible changes in diet and quality of life among breast cancer patients and also to obtain the perspective of medical professionals. Part II was a survey using a food frequency questionnaire and 24 hour diet recall to assess dietary changes and European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 version 3.0 and BR23 questionnaire to assess QOL changes in breast cancer patients. The breast cancer patients were recruited before the confirmation of their diagnosis and interviewed again 6 months +/- 9 months/12 months after diagnosis.
Results showed that the women commonly changed their dietary pattern and use of supplements. Increased consumption of omega-3 and decreased consumption of durian, trans-fats, tea, coffee and wine were all associated with a positive change in quality of life.
Dietary changes were commonly observed in breast cancer patients in Hong Kong. However, patients’ perception of the necessary dietary changes was not matched with the health professionals’ expectations. Long-term effects of the common food items that patients avoided or increased consumption needs further exploration.
Plain language abstract
Changes in dietary intake and consumption of supplements are associated with changes in quality of life of breast cancer survivors.
The world-wide incidence of breast cancer has increased in the past decades. Due to early detection and advancement in modern medicine, the global mortality rate of breast cancer has decreased gradually with effective treatment. Dietary changes and the use of supplements are common in breast cancer survivors. Currently there is very little documentation of how women might change their food and supplement consumption including herbal use after the diagnosis of breast cancer; what leads to these changes and what impact these changes has on their quality of life.
The study had two parts. Part 1 was a focus group discussion exploring attitudes and opinions towards the possible changes in diet and quality of life among breast cancer patients and also medical professional’s perspectives. Part II was a survey using a food frequency questionnaire, 24 hour diet recall and questionnaire to assess the changes in diet and quality of life in breast cancer patients. The breast cancer patients were recruited before the confirmation of their diagnosis and interviewed again at 6 months +/- 9 months/12 months after the diagnosis.
The study showed that breast cancer patients commonly changed their diet after diagnosis. Most of these changes involve the adoption of a healthier lifestyle such as decreased fat intake, decreased caffeine and alcohol intake and increased vegetable consumption. However, some of these changes are simply due to cultural and health beliefs. For example, in Chinese culture, poultry, beef, certain kinds of fruits and seafood are believed to be “toxic” and bad for one’s health. Therefore, these kinds of food were also shown to have decreased intake in our study.
Our study showed increased consumption of Omega-3 was associated with a positive change in quality of life. On the other hand, decreased consumption of durian, trans-fats, tea, coffee and wine were also associated with improved quality of life. There were no consistent or significant effects on quality of life with most of the food/nutrients or supplements that were avoided or where consumption was increased by breast cancer patients.
Our study has documented the pre and post diagnosis changes in breast cancer dietary changes and their effect on quality of life. Breast cancer patients should be advised to adopt a healthy and balanced diet.