Multivitamin Use Linked To Increased Breast Cancer Risk

Oops.

Researchers in Sweden who studied data on over 35,000 middle aged and older women followed for 10 years found a link between taking multivitamins and increased risk of breast cancer and said this was of concern to public health and should be investigated further...

Many women use multivitamins in the belief that they will protect them from chronic diseases like cancer and heart disease, wrote the authors in their background information...

The results showed that:

974 women were diagnosed with incident breast cancer over a mean follow up of 9.5 years.

293 of the diagnoses were among 9,017 women who reported using multivitamins.

Use of multivitamins was linked to a statistically significant 19 per cent increased risk of breast cancer (after adjusting for lifestyle and risk factors like weight, diet, smoking, exercise, and family history of breast cancer, the relative risk of women who reported using multivitamins was 1.19, with confidence interval ranging from 1.04 to 1.37).

Hormone receptor status did not change the strength of this link significantly.

The authors concluded that:

"These results suggest that multivitamin use is associated with an increased risk of breast cancer. This observed association is of concern and merits further investigation."

Still think they have any idea what a "safe" supplement is?