Well, you have to draw a distinction here between physical and psychical addiction. You can get phsychically addicted to anything, substances that cause physical addiction are a bit different. And generally bad for you, even if the only side effect are the withdrawal symptoms. And the most potent ones can actually cause withdrawal symptons so sever that it's impossible to ever get off them. Opiates are an example.
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It's difficult, but not impossible. I assure you.
Secret IMF Cheif: Can you do it?
Ethan Hunt: It will be difficult.
Secret IMF Cheif: Well, this is Mission Impossible, not Mission Difficult. This should be a walk in the park for you.