Datagrid Style Formatting

I have a DataGrid component in CS3 that pulls from an XML file that is working fine, but I wanted to make the text size in the columns larger because there are some older people that will be viewing it when completed. I was successful in changing the Heading text size/format by doing the following:

var tf:TextFormat = new TextFormat();
tf.size = 14;
tf.bold = true;
tf.font = "Verdana";
tf.color = 0xff0000;
myData.setStyle("headerTextFormat", tf);

This sets the Header columns to Red size 14 Veranda text just fine.

I have looked all over the net trying to find how to target the columns text so I can change the size, does anyone know if this is possible or have a solution?