Building a healthier Britain. Part 3, Breast cancer.

The first in a four-part series in which Richard Hannaford looks at how since the 1950s doctors have continuously researched people's health and lifestyle, leading to epidemiological studies, the results of which we can perhaps now begin to assess. This part focuses on breast cancer. Most of our current information comes from epidemiological studies like the Million Women's Study and the Women's Health Initiative. We know, through these studies, that 5% of cases are due to hereditary gene problems, that breastfeeding and childbirth protect against breast cancer and Hormone Replacement Therapy can produce an increased risk.