1. To determine if levels of fats, damaged or oxidized fats, oxidized or damaged vitamins and vitamins (8-isoprostane, cholesterol, fatty acids, tocopherols, carotenoids and 2,6-cyclolycopene-4,5-diol) can be quantified in breast NAF obtained before breast lavage. Levels in NAF will be compared to that in blood. These measures were chosen based on their potential relationships to dietary intakes and to oxidative stress levels, which is relevant to intervention studies. Tocopherols and carotenoids are dietary antioxidants, and certain fatty acids are oxidized more readily than others. Both 8-isoprostane and 2,6-cyclolycopene-4,5-diol appear to be markers of oxidative stress.