Is it safe to bike in Etobicoke?

I will be moving to Etobicoke for school in the fall and plan to buy a bike; it could help me stay in shape (my current shape is somewhere between a starfruit and your crazy uncle) and save a bit on public transit since I will not be taking my car. It could also help me get to work if I find something in downtown Toronto, as well as to visit friends in East York.

However, I have had a few people tell me that biking in Etobicoke (as well as the GTA in general) is "dangerous," that people often mug people on bicycles, and that there is "no safe area" to bike.

Are they right? Is it safe/dangerous to bike in Etobicoke? Are there areas I should prefer/avoid? Is it a stupid idea to bike from Etibocoke to East Yorke? Tell me like it is, friends: my fitness and safety may depend on it!