Tea and citrus flavonoids may lower ovarian cancer risk

29-Oct-2014 - Last updated on 29-Oct-2014 at 12:43 GMT

"This is the first large-scale study looking into whether habitual intake of different flavonoids can reduce the risk of epithelial ovarian cancer,”

Flavonoids from tea and citrus fruits and juices may be associated with a lower risk of developing ovarian cancer, according to new research.

The study, published in the American Journal of Clinical Nutrition, suggests that women who consume foods containing certain dietary flavonoids significantly decrease their risk of developing epithelial ovarian cancer, the fifth-leading cause of cancer death among women.

Led by Professor Aedín Cassidy from the University of East Anglia (UEA) in the UK, the team found that those who consumed food and drinks high in flavonols (found in tea, red wine, apples and grapes) and flavanones (found in citrus fruit and juices) were less likely to develop the disease.

"This is the first large-scale study looking into whether habitual intake of different flavonoids can reduce the risk of epithelial ovarian cancer,” said Cassidy.

"We found that women who consume foods high in two sub-groups of powerful substances called flavonoids – flavonols and flavanones – had a significantly lower risk of developing epithelial ovarian cancer.”

Study details

Cassidy and her team studied the dietary habits of 171,940 women aged between 25 and 55 for more than three decades. All of the women took part in the Nurses’ Health Study and Nurses’ Health Study II.

The team analysed food intakes and health outcomes from the participants to examine associations between intakes of total flavonoids and their subclasses (flavanones, flavonols, anthocyanins, flavan-3-ols, flavones, and polymeric flavonoids) and risk of ovarian cancer.

The team revealed that total flavonoids were not statistically significantly associated with ovarian cancer risk. However, participants in the highest quintiles of flavonol and flavanone intakes had modestly lower risk of ovarian cancer than that of participants in the lowest quintile, they said.

"A couple of cups of black tea every day was associated with a 31% reduction in risk,” noted the team.

Intakes of other subclasses were not significantly associated with risk, they added.

Source: American Journal of Clinical Nutrition
Published online ahead of print, doi: 10.3945/ajcn.114.088708
“Intake of dietary flavonoids and risk of epithelial ovarian cancer”
Authors: Aedín Cassidy, et al