In your situation your best bet is to simply diffuse the situation by telling people exactly what they don't want to hear. Tell them you gave up your social life for 6 months and spent your free time training and being meticulous about your diet. Explain how you eat 40 grams of protien every 3 hrs and never miss a workout. Explain to them that they can do it to if they'd just give up all of the things in life that they enjoy too-which ain't gonna happen. This is passive aggressive at it's best. By explaining to them your hard work and discipline in detail, it will probably make them feel like shit that they don't possess the mental strength that you have to attain fitness. Avoid the topic of juice when it comes up-laugh it off-or make jokes about horses, etc. They'll be dying to hear that you use them-so deny it. It's not like they give a fuck about your health. They just wanna be able to gossip with others and say that they heard from your own mouth that you are a cheating, roid abusing, felon(not a great resume builder) so they can feel better about their own pathetic lives.
Personally, I just avoid contact with anyone that doesn't accept me for who I am. Fortunately I don't have a boss or coworkers to worry about-but I realize that most people don't have that luxury.
Still, prepare for the worst. It's coming. Almost everyone I know that has a job surrounded by fat ass, sedentary lifestyle types end up being persecuted by their coworkers and boss for being into fitness. Just the mere sight of you makes most of them want to cry. Revenge is sweet-but it's not gonna help you climb the corporate ladder any faster in most workplaces.