Multivitamins and Breast Cancer
NPNZ Media Release 19 April 2010
Study claiming multivitamins link to breast cancer is alarmist
Natural Products New Zealand (NPNZ), the industry body representing a significant proportion of New Zealand natural health product manufacturers, says consumers should not be alarmed over media reports of a study claiming a link between multivitamin use and an increased risk of breast cancer.
The Swedish study1 which collected data by a self-administered questionnaire suggested an association between the use of multivitamins and an increased risk of breast cancer.
NPNZ questions the validity of the study and believes consumers should not stop taking multivitamins.
Michelle Palmer, executive director of NPNZ says the Swedish survey of 35,000 women is not conclusive and contains several limitations.
“The fact that the whole study is based on a self-administered questionnaire means there is a high possibility of difficulty in accurately recalling details and errors in classification by the researchers leading to skewed results,” says Ms Palmer.
“There are no details on types of multivitamins provided for this study and the researchers were not able to identify the components of multivitamins that may be responsible for the possible association.
“There are many more robust studies whose findings do not support this claim.”
The Women’s Health Initiative2 which followed over 68,000 women for eight years showed there was no association of multivitamin use and the risk of cancer.
A population based study published in 2009 found no association between multivitamin use and breast cancer.3
1 Larsson et al. Multivitamin use and breast cancer incidence in a prospective cohort of Swedish women. March 24:10.3945/ajcn.2009.28837.
2 Neuhouser ML, Wassertheil-Smoller S, Thompson C, et al. Multivitamin use and risk of cancer and cardiovascular disease in the Women’s Health Initiative cohorts. Archives of Internal Medicine 2009; 169:294-304.
3 Meulepas JM, Newcomb PA, Burnett-Hartman AN, et al. Multivitamin supplement use and risk of invasive breast cancer. Public Health Nutrition 2009; Dec3:1-6.