‘Mate’ Intake, Hormone-Based Risk Factors and Breast Cancer: a Case-Control Study

Document Type: Research Articles

Authors

1 Unit of Oncology and Radiotherapy, Pereira Rossell Women's Hospital, Bvar.Artigas 1550, Montevideo 11300, Uruguay.

2 IUCLAEH School of Medicine, Prado and Salt Lake, Maldonado 20100, Uruguay.

3 Biomedical Sciences Center, University of Montevideo, Puntas de Santiago 1604, Montevideo 11600, Uruguay.

4 Endocrinology and Metabolism Department, Clinical Hospital, UdelaR State University, Av.Italia s/n y Las Heras, Montevideo 11300, Uruguay.

Abstract

Previous reports on the inverse association between ‘mate’ intake (infusion of Ilex Paraguariensis herb) and breast
cancer (BC) risk led us to consider two main roles for the infusion: as a substantial antioxidant contributor and as
a hormone regulator, particularly through anti-aromatase capacities. Since menstrual-reproductive risk factors for
BC reflect women’s estrogenic exposure during the reproductive lifespan, and considering that ‘mate’ intake exerts
putative stronger protection among high antioxidant contributors, we attempted to analyze interactions among the
infusion, hormon-linked reproductive factors and BC risk, which have hitherto remained unexplored. We analyzed a
database of 572 BC incident cases and 889 controls. Women were interviewed with a specific questionnaire featuring
socio-demographic, lifestyle and reproductive variables (age at menarche, 1st live birth and menopause; number of live
births; breastfeeding months), and a food frequency questionnaire, focusing on ‘mate’ intake (consumer status, daily
intake, age at start, age at quit, duration of habit). Odds ratios (OR) and their 95% confidence Intervals were calculated
through unconditional logistic regression, adjusting for relevant potential confounders. ‘Mate’ intake showed strong
inverse associations with some high-risk hormone-related factors: early menarche, nulliparity, low breastfeeding, long
reproductive years and high number of ovulatory cycles. Moreover, all subsets of high dietary energy demonstrated
even stronger associations. In conclusion, regarding exposure to known hormone risk factors, we found strong inverse
associations between high ‘mate’ intake and BC, which were greater among those consuming higher calorific diets.
Our analyses support possible combined antioxidant and antiestrogenic effects for ‘mate’ infusions.

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