Breast Cancer Risk Research Analysis

Summary of Breast Cancer Risk

Scientific Information on Breast Cancer Risk

The Human Effect Matrix looks at human studies (it excludes animal and in vitro studies) to tell you what supplements affect breast cancer risk

Grade	Level of Evidence [show legend]
	Robust research conducted with repeated double-blind clinical trials
	Multiple studies where at least two are double-blind and placebo controlled
	Single double-blind study or multiple cohort studies
	Uncontrolled or observational studies only

Outcome	Magnitude of effect ? The direction and size of the supplement's impact on each outcome. Some supplements can have an increasing effect, others have a decreasing effect, and others have no effect.	Consistency of research results ? Scientific research does not always agree. HIGH or VERY HIGH means that most of the scientific research agrees.	Notes
Vitamin E	-	Very High See all 3 studies	No significant protective effect of 600 IU vitamin E every other day in otherwise healthy women for preventing the development of breast cancer.
Ginkgo biloba	Minor	- See study	An increase in breast cancer risk has been noted to barely pass statistical significance in an analysis of cancer development in elderly persons (75 years or older) given EGb-761 daily for a median 6.1 years.
Vitamin D	Minor	Very High See 2 studies	There is less risk of breast cancer associated with Vitamin D supplementation
Melatonin	-	- See study	Too preliminary to conclude any relation to breast cancer, but urinary melatonin metabolites are positively correlated with breast cancer risk (not applied yet to supplementation)

All comparative evidence is now gathered in our A-to-Z Supplement Reference.

The evidence for each separate supplement is still freely available here.