1. Never wear a Wire bra. Always wear wireless, and only wear a bra when you need to. The constriction blocks the lymph nodes and allow toxins to build up.
2. Breastfeed. 2 years of breastfeeding cuts your risk by 50%, and the longer you breastfeed, the smaller the risk. If you have children, and you don't breastfeed, that greatly increases your risk, so you definitely need to be very proactive.
3. Help your hormones. Chlorophyll, Royal Jelly and Maca Root are all helpful hormone balancers.
4. Fatty acids from fish, coconut and avocadoes also help. Antioxidant rich foods are obviously something to be aware of. Also be aware of your nutritional type (Dr. Mercola's website has a good example).
5. No aluminum-based deodorants. Try different natural types of deodorant (Jason's, Kiss my face, Queen Helene, Arm & Hammer Essentials) until you find one you like. There are also a lot of recipes out there to make your own out of coconut oil, baking soda and essential oils.
6. Very obviously - no skin care products that have chemicals or names you can not pronounce. Those are all toxic to your cells. It amazes me how many people still use name brand toxic chemical cleaners, like Lysol, Dove, Ivory, etc. Anything that has Sodium Lauryte Sulfate - you need to avoid! Use natural or organic cleaners only - for the household, for your laundry, and for your skin. There are many cheap ways to do this - you can easily make your own if necessary - there are many recipes online.
7. Learn to use natural God made medicines (not chemical man-made medicines - it amazes me how many people put all their faith in man-made chemical "prescription" medicines). Take some essential oil classes, or peruse the many websites. Learn more about homeopathy, herbs, chinese medicines, and the healing power of certain foods (organic chicken broth and raw goats milk are incredible gut healers).
8. And of course, try to eat as organically as your budget allows. Look up your neighborhood food co-ops for produce, raw dairy, and grass-fed meat. Facebook and Meetup people will be happy to help you find your local co-ops.
9. Never get a mammogram. They are often 50% false positives. And if you do have breast cancer, the constriction of a mammogram spreads the cancer! Join other women as they battle the billion dollar industry and fight against this archaic and barbaric practice. If you want a diagnosis, use thermogram technology for a safer and more accurate report.
Here is a great all-in-one article: http://realhealthtalk.com/Breast_Cancer_Lecture_Notes.html