Weight Loss Decreases Risk Of Breast Cancer In Susceptible Women

Steven Narod from the University of Toronto, Canada, and colleaguesfrom universities in Canada, the USA and Poland studied two groups ofwomen, all of whom had a mutation in one of the breast cancersusceptibility genes BRCA1 and BRCA2. The first group had beendiagnosed with breast cancer while the second group had not. Eachmember of the first group was paired up, or 'matched', with a womanfrom the second group who was the same age, carried a mutation in thesame gene and lived in the same country. This is the largest study ofthis kind to date, with 1073 women from five different countries ineach group. By comparing the two groups, the researchers could identifythe relationship between the incidence of breast cancer before themenopause in women at risk, and weight at 18, 30 and 40 years of age.

Their results show that, for women who have a mutation inBRCA1, "weight loss of at least 10 pounds was associated with a 65%reduction in cancer risk between ages 30 and 40." The study also showsthat BRCA1 mutation carriers who gained 10 pounds or more between 18and 30 years of age are 44% more at risk of developing breast cancer ifthey have 2 children or more. No association between weight loss andbreast cancer risk was shown in BRCA2 mutation carriers.

Article:
Changes in Body Weight and the Risk of Breast Cancer in BRCA1 and BRCA2 Mutation Carriers
JoanneKotsopoulos, Olufunmilayo I. Olopado, Parviz Ghadirian, Jan Lubinski,Henry T. Lynch, Claudine Isaacs, Barbara Weber, Charmaine Kim-Sing,Peter Ainsworth, William D. Foulkes, Andrea Eisen, Ping Sun, Steven A.Narod
Breast Cancer Research 2005, 7:R833-R843