A study out of the Susan F. Smith Center at Dana Farber Cancer Institute has demonstrated that flaxseed extract, which contains a high level of lignans (chemical compounds which are similar to estrogen and are associated with a higher risk of breast cancer,) may actually help block cancer cell growth resulting from stronger forms of estrogen.
As for Vitamin D, which has demonstrated some anti-cancer properties already, 2,000 IU's were given daily for 1 year to healthy, premenopausal women to help further explore the effects of this as a preventative measure.
Incorporating flaxseed and Vitamin D into your diet, vegan or otherwise, is easy, and at no risk. I take Vitamin D regularly (especially when I don't have the luxury of spending a lot of time in the sun,) and flaxseed can be easily tossed into salads, cereals, and smoothies. You may need to carry a little dental floss as some of those seeds may show in your smile, but you get increased benefits in your diet without compromising the taste of the foods you already love.
