TUESDAY JAN 8, 2008 (Foodconsumer.org) -- Eating meat may increase risk of breast cancer and the elevated risk was particularly significant in women who carry certain genes that activate meat-born toxins quickly, according to a new Danish study in the Feb 2008 issue of European Journal of Cancer Prevention.

The study led by Egeberg R. and colleagues from a number of Danish organizations showed that daily intake of every 25 grams of total meat, red meat and processed meat was associated with 9, 15, and 23 percent increase in breast cancer risk, respectively.

photo credit: cancer.gov

The case-control study involved 378 breast cancer cases and the same number of controls who were identified among 24,697 postmenopausal women included in the 'Diet, Cancer and Health' cohort study during the period of 1993 to 2000.

The study meant to examine the effect of polymorphisms in N-acetyl transferase 1 and 2 on the risk of breast cancer showed that the risk was largely confined to intermediate/fast N-acetyl transferase 2 acetylators, suggesting that the elevated risk was only confined to genetically susceptible women.

The results from the current study seem to be contradictory to at least one early study which found no association whatsoever between consumption of meat or cooking method and risk of breast cancer and women with fast acetylators N-acetyl transferase 2 genotypes were not at higher risk of breast cancer due to consumption of meat.

That study was led by Gertig DM and colleagues from Department of Medicine, Brigham and Women's Hospital and Harvard Medical School and published in the January 1999 issue of the International Journal of Cancer.

Gertig's study involved 466 breast cancer cases whose blood samples were analyzed between 1989 -1990 and June 1, 1994 and the same number of controls. Both cases and controls were from 32,800 women participating in the Nurses' Health Study.

The chemicals of concern are heterocyclic amines or HAs generated during cooking of meat and animal protein at high temperature, which are known potent human carcinogens. It's believed that metabolism of HA is influenced by polymorphisms in the N-acetyl transferase 2 gene.

Gertig and team acknowledged that "we cannot exclude misclassification of HA intake as the reason for the lack of association" between meat consumption and increased risk of breast cancer.

A more recent Dutch study published in the April 2004 issue of Cancer Causes & Control observed that intermediate and high consumption of red meat increased risk of breast cancer by 79 and 46 percent respectively in postmenopausal women, but the reliability could not be tested as the number of breast cancer cases (229) was not big enough.

The study led by van der Hel OL and team from Julius Center for Health Sciences and Primary Care, University Medical Center in Utrechtm, The Netherlands showed that polymorphisms in N-acetyl transferase 1 and 2 and Glutathione s-transferase M1 and T1 do not modify the association between red meat consumption and risk of breast cancer.

The researchers found women who did not carry GSTM1, which is known to be a detoxifying enzyme, were 46 percent more likely to develop breast cancer.  Those with the genotype would slightly increase their risk of breast cancer by consuming red meat.

A scientist affiliated with foodconsumer.org advised that readers exercise caution when it comes to meat consumption because not all studies are equally trustworthy and technically reliable.  An association between meat consumption and risk of the cancers in addition to breast cancer has been reported.  The bottom-line is that HAs are carcinogens officially recognized by the United States government and consumers should by all means avoid as much as they can.


Source:

Egeberg R, Olsen A, Autrup H, et al. Meat consumption, N-acetyl transferase 1 and 2 polymorphism and risk of breast cancer in Danish postmenopausal women. Eur J Canc Prev. 2008;17:39-47.

© 2004-2008 by foodconsumer.org unless otherwise specified

Top of Page

	Web foodconsumer.org

Search Consumer-friendly Health Sites

Watch the latest videos on YouTube.com