Previous studies suggest that diets high in soy foods rich in isoflavone phytoestrogens may reduce the risk of breast cancer. Lignans are bioactive plant estrogens found in plant foods such as flaxseed, tea, coffee, fruits, vegetables and grain products (bread, breakfast cereals, rice and pasta). However, soy isoflavones are plant estrogens that aren't lignans. Now research reports that a high daily intake of plant foods rich in lignans may decrease the risk of breast cancer after menopause.
The study, published in the Journal of the National Cancer Institute, investigated whether dietary intake of plant lignans is associated with the risk of breast cancer. Researchers at the Institut National de le Sante et de la Recherche (INSERM) in France, analyzed the data of 58,049 postmenopausal French women not taking soy isoflavone supplements. The participants were followed from 1993 to 1997. Food frequency questionnaires obtained from the participants were analyzed to determine nutrient intake.
The researchers found that 1,469 participants developed breast cancer during the follow-up period. Findings revealed that participants with the highest lignan intake had a 17 percent decreased risk of breast cancer, compared to those with the lowest intake. However, high lignan intake was only associated with a lowered risk of estrogen (ER) and progesterone (PR) linked breast cancers.
"High dietary intakes of plant lignans and high exposure to enterolignans were associated with reduced risks of ER- and PR-positive postmenopausal breast cancer in a Western population that does not consume a diet rich in soy," the study authors conclude.
REFERENCES:
1. Touillaud MS et al. Dietary lignan intake and postmenopausal breast cancer risk by estrogen and progesterone receptor status. JNatl Cancer Inst 2007 Mar 21;99(6):475-86.
Posted by Elaine Gavalas on March 28, 2007 02:53 PM
