Rock County, family living educator for the University of Wisconsin extension, Angela Flickinger says you should follow three basic tips to keep your family healthy.
One is to wash all produce before eating. She says, "you don't know who's handled your food" before you buy it. The second tip is to go right home after buying items from a grocer or farmers' market so meat and eggs can be refrigerated quickly. And finally, fruit and vegetables require varying temperature and humidity levels for proper storage.
Details can be found at http://learningstore.uwex.edu/pdf/A3823.pdf