The junk food could indicate that you are actually feeling hungry during your dream. The junk food could also show that you feed yourself with the bad food. Your body is giving you a signal. The junk food could be used as the metaphor for people you are surrounded by or the relationships youve got yourself into. If you ate too much of the junk food, you should reconsider your life, perhaps you are sick of everything.
Read more about dreaming of Junk food in other dream meanings interpretations.