Rates of breast cancer are rising in young women. Why? Dr. Eleonora Teplinsky joins "Healthful" to explain the possible lifestyle factors and environmental exposures. She discusses what we can do to lower our risks. Plus, there's new research about why dense breasts may increase cancer risk. 50% of women have dense breasts, including Norah, and many have no idea. Dr. Teplinsky tells you what to ask for to find out if you're a part of that population.