Smoking ANY number of cigarettes at or before age 16 could quadruple your chance of getting breast cancer later in life. Girls who smoke and have a weak version of a cancer-neutralizing enzyme -- which millions of American women have -- see their risk for breast cancer skyrocket. More than 55 percent of whites, 35 percent of blacks and 10 to 20 percent of Asians have the weak gene, according to a Journal of the American Medical Association study.

("Smoking linked to breast cancer," The New York Times, 11/13/96; "Focus Smokeout on teen girls," Oakland Tribune, 11/19/96.)