Wednesday, May 05, 2010

Multivitamin supplements unrelated to breast cancer risk in large U.S. study

A recent Harvard Medical School study followed more than 37,000 U.S. women for 10 years and found no correlation between multivitamin use and breast cancer risk.

Researchers from Harvard Medical School and Brigham and Women’s Hospital recently evaluated possible associations between multivitamin supplements and risk of breast cancer. At the beginning of the study, 37,920 cancer-free U.S. women aged 45 and older provided detailed information on multivitamin supplement use. Throughout an average of 10 years of follow-up, 1,171 cases of breast cancer were documented.

The use of multivitamin supplements was not associated with an overall risk of breast cancer in this large study group. High frequency of use (at least 6 times per week) and duration of supplementation (current use for at least 20 years) were not associated with an increase in risk compared to non-users. A small reduction in breast cancer risk was seen in multivitamin users who consumed 10 grams/day of alcohol or more. There was also a slight decrease in risk of estrogen receptor negative-progesterone receptor negative breast cancer among multivitamin users.

The researchers stated that although there was no overall statistically significant association between multivitamin use and breast cancer, multivitamins may reduce the risk for women consuming alcohol and in certain estrogen receptor negative cancers.