WeeklySA_AdminSURVIVAL: A long-term study suggests that higher consumption of polyphenols—plant compounds abundant in coffee and many whole foods—may be associated with better survival after breast cancer. Researchers caution, however, that the findings do not prove cause and effect…
By Own Correspondent
ABOUT 694 000 women worldwide died from breast cancer in 2024, highlighting the continuing need for better prevention, treatment and survivorship strategies.
Breast cancer is the most commonly diagnosed cancer among women globally and one of the leading causes of cancer-related death. Survival prospects vary according to the type and stage of the disease, whether it has spread to other parts of the body, and how it responds to treatment.
Alongside prescribed medical care, research suggests that healthy lifestyle choices—including regular physical activity and a balanced diet—may support the health of women diagnosed with breast cancer.
Previous studies have examined whether nutrients such as B vitamins, vitamin D, vitamin C and omega-3 fatty acids could influence breast-cancer outcomes.
This study identifies an important signal, but it does not establish that increasing polyphenol intake will prevent recurrence or extend survival…
Now, a study published in the British Journal of Nutrition suggests that polyphenols—natural plant compounds known for their antioxidant and anti-inflammatory properties—may be associated with a lower risk of breast-cancer recurrence and death.
Researchers followed 95 women diagnosed with breast cancer for an average of 11.5 years and assessed the amount of polyphenols in their diets.
They found that women with a higher overall intake of polyphenols, particularly phenolic acids and lignans, had a lower risk of dying from breast cancer.
Higher consumption of phenolic acids was also associated with a reduced risk of the cancer returning. Greater total polyphenol intake was linked to longer survival when deaths specifically caused by breast cancer were considered.
Coffee emerged as the main source of total polyphenols, phenolic acids and lignans among the women who participated in the study.
The finding does not, however, prove that coffee directly prevents breast-cancer recurrence or death. The research was observational and involved a relatively small group of women, meaning that it could identify associations but not establish cause and effect.
Polyphenols are found in a broad range of plant-based foods and drinks, including berries, cocoa, coffee, colourful vegetables, extra-virgin olive oil, herbs, spices, legumes, nuts and seeds.
Monique Richard, a registered dietitian nutritionist and owner of Nutrition-In-Sight, said polyphenols were consumed as part of foods containing many other beneficial nutrients.
“Polyphenols don’t exist in isolation in nature,” Richard told Medical News Today. They are accompanied by fibre, vitamins, minerals, healthy fats and numerous other plant compounds that may work together.
Richard, who was not involved in the study, said polyphenols could influence several biological processes relevant to cancer survival. These include oxidative stress, chronic inflammation, insulin sensitivity, immune signalling, the formation of new blood vessels and communication between cells.
HORMONAL EFFECT
Dietitian Meridan Zerner said polyphenols may help limit damage caused by unstable molecules known as free radicals and moderate prolonged inflammation—conditions that could contribute to cancer progression.
Polyphenols may also affect the composition and activity of bacteria in the digestive system.
Zerner said lignans, one of the polyphenol groups highlighted in the research, could support gut bacteria in ways that might reduce oestrogen-driven growth in breast tissue.
More research would be required to determine whether such a hormonal mechanism was responsible for the association observed in the study.
Experts have welcomed the findings but stressed that women should not interpret them as a reason to drink excessive amounts of coffee.
Tracy Crane, co-lead of the Cancer Control Programme and director of lifestyle medicine, prevention and digital health at the Sylvester Comprehensive Cancer Centre in the United States, described the results as encouraging and biologically plausible.
However, Crane said they should be regarded as generating a hypothesis for further investigation rather than providing definitive evidence.
“This study identifies an important signal, but it does not establish that increasing polyphenol intake will prevent recurrence or extend survival,” she said.
The findings also did not mean that women should begin consuming large quantities of coffee—or alcohol, which may contain some polyphenols—to obtain these compounds.
FURTHER STUDIES
Crane called for the research to be replicated in much larger and more diverse populations, with participants’ diets assessed repeatedly before and after diagnosis.
Future studies should account for factors that may influence breast-cancer outcomes, including the cancer subtype and stage, treatment received, adherence to treatment, body weight, physical activity, existing health conditions and socioeconomic circumstances.
Researchers would also need to establish whether increasing amounts of polyphenols produce progressively greater benefits and distinguish the possible effects of coffee from those of a person’s broader diet.
Crane said food-based clinical trials could investigate whether increasing the consumption of a diverse range of polyphenol-rich whole foods alters metabolic, inflammatory and tumour-related processes.
If such trials included enough participants and followed them for sufficiently long periods, they might eventually establish whether these foods influence breast-cancer recurrence and survival.
For now, the findings support eating a varied, plant-rich diet as part of an overall healthy lifestyle—but do not justify replacing proven cancer treatment or taking concentrated polyphenol supplements without medical advice. – MNT
