Bite over food

Question
Help, My golden retreiver had always growled when she was eating ab=nd you got near her food but recentely she bit my 20 mth old in teh hand and just today bit me on the arm for trying to move her treat off the carpet. She has been on a diet for a few months which made her obviously more protective of her food. I diont want to get rid of her but dont know what to do to rectify the matter. Now I am afraid of her biting us more. Can you help

Answer
"Might you have any suggestions on using the positive approach to make her not so aggressive when people walk past the yard...she was trained never to leave the year and knows her boundries but is still intimidating when people walk past our home also if someone comes tpo the door...most of teh time in this case when they enter she is fine but sometimes she just keeps barking?"


Another article addressing this problem:


http://www.marinhumanesociety.org/Behavior/Handouts/DifficultDog.pdf