Red meat linked to Breast Cancer Risk - Study

A prospective study conducted to understand breast cancer probability among premenopausal women reveals that, greater red meat intake elevated risk for an estrogen-linked form of breast cancer medically known as hormone receptor-positive breast cancer.

Researchers from Brigham and Women's Hospital and Harvard Medical School in Boston found that consumption of more than one-and-a-half servings of red meat per day by women almost doubled their vulnerability of developing breast cancer as compared with those who ate three or fewer servings per week.

Breast cancers are malignancies that develop in breasts of women. Either one or both breasts can be affected by these cancerous growth. These breast cancer cells may contain receptors for hormones like estrogen or progesterone.

Cells containing these receptors are known as 'hormone receptor-positive cells' and if they lack them are called 'hormone receptor-negative cells'.

Hormone receptor-positive cells spur the growth of breast tumors because of their affinity for estrogen and progesterone hormones. These hormones attach with positive receptor cells and then guide cells to grow and divide.

An estimated 2.6 million women have been detected for breast cancer in the United States. About two-thirds of breast cancers detected are of hormone receptor-positive type.

Under the study led by Dr Eunyoung Cho, red meat intake and breast cancer risk were assessed among premenopausal women aged 26 to 46 years in the Nurses' Health Study II. The researchers excluded postmenopausal women and those who had cancer.

During the 12 year study, food frequency questionnaire were filled in by 90, 659 respondents in 1991, 1995, and 1999 and 2003, to assess the intake of red meat along with 130 other foods and beverages.

Breast cancers were self-reported and confirmed by review of pathologic reports every two year.

On completion of the study, results reported 1,021 cases of breast cancer, out of which 512 women had reportedly developed cancer of the category oestrogen and progesterone-receptor positive.

Published in the November issue of ‘Archives of Internal Medicine’, Dr Eunyoung Cho , however, believes that several biological mechanisms can explain the positive link between red meat intake and hormone receptor-positive breast cancer risk.

Out of the numerous reasons put forward to explain the positive link, ‘heterocyclic amines’- a cancer causing chemical present in cooked and processed red meat and created during cooking of red meat, is one of them.

A second potential reason is the growth hormones administered to cattle in the US, though not used in Europe.

Moreover, red meat is a source of heme iron, which according to previous studies spurs up the growth of hormone receptor positive tumors.

However, nurse specialist at Breast Cancer Care, Maria Leadbeater quoted, "The benefits of eating a healthy and varied diet are well established and the biggest risk factors for breast cancer remain gender and increasing age."