From the Guidelines
Post-diagnostic coffee and tea consumption has no clear association with breast cancer survival based on the provided evidence. The most recent and highest quality study, 1, does not mention coffee and tea consumption in relation to breast cancer survival. However, it does emphasize the importance of physical activity, weight management, and a healthy diet in improving breast cancer outcomes.
Key Points to Consider
- The study 1 highlights the benefits of physical activity, both pre- and post-diagnosis, in reducing the risk of breast cancer-specific and all-cause mortality.
- It also suggests that more healthful dietary patterns after diagnosis are associated with lower risk of overall and nonbreast cancer mortality.
- While the study 1 discusses the importance of nutrition and physical activity during and after cancer treatment, it does not provide specific information on coffee and tea consumption.
- In the absence of direct evidence, it is essential to focus on established factors that improve breast cancer survival, such as physical activity, weight management, and a balanced diet.
Recommendations for Patients
- Patients should prioritize physical activity and maintain a healthy weight to improve breast cancer outcomes.
- A balanced diet with an emphasis on whole foods, fruits, and vegetables is recommended.
- Patients should discuss their dietary habits, including coffee and tea consumption, with their healthcare providers to ensure they are making informed choices that complement their conventional breast cancer treatments.
From the Research
Post-Diagnostic Coffee and Tea Consumption
- Post-diagnostic coffee consumption has been associated with lower breast cancer-specific mortality and all-cause mortality in women with breast cancer 2
- Higher post-diagnostic coffee consumption (>3 cups/day) was associated with a 25% lower risk of breast cancer-specific mortality and a 26% lower risk of all-cause mortality 2
- Post-diagnostic tea consumption (>3 cups/day) was associated with a 26% lower risk of all-cause mortality 2
Patterns of Coffee and Tea Consumption
- A longitudinal study of patients with breast cancer identified four stable patterns of coffee and tea consumption: "Low", "Moderate", "High", and "Very high" 3
- Patients in the "Very high" group (>4 cups of coffee and/or tea per day) were more likely to be younger, smokers, with higher monthly income and education 3
- No association was found between higher consumption of coffee and/or tea and worse patient-reported outcomes and clinical outcomes 3
Green Tea Consumption and Breast Cancer
- A systematic review and meta-analysis found that green tea consumption may possibly help prevent breast cancer recurrence in early stage (I and II) cancers 4
- The pooled relative risk of developing breast cancer for the highest levels of green tea consumption was 0.89, but this was not statistically significant 4
- Dose-response relationships were evident in only 3 of the 7 studies, and conclusions as to the potential therapeutic application of green tea are currently impossible to make due to the small number of studies conducted 4
Coffee Consumption and Breast Cancer Risk
- A narrative review found that most of the existing literature reports no association or a slight negative association between coffee consumption and the risk of developing breast cancer 5
- Coffee consumption was inversely associated with breast cancer risk in postmenopausal women and in women carrying a BRCA1 mutation 5
- A systematic review and network meta-analysis found that low-dose coffee intake and high-dose tea intake may exhibit efficacy in preventing ER-negative breast cancer, particularly in postmenopausal women 6