How do I approach my 23 yr old college son about his smoking?

He's probably afraid you'll spaz out, and isn't telling you.

Just leave him be. He's old enough.

When you talk to him make sure you treat him with respect and talk to him like he is an adult. Show him that it is not only hurting him by smoking, it is also hurting you as a parent. Tell him how it makes you feel and hopefully he will respect your emotions enough to quit but with people addicted to nicotine, its not an easy task to quit, nor is it an easy task to actually get someone to try and quit. best of luck

Tell him you know about his smoking and your concerned about his health, but ultimately it's his decision. Good luck! Smoking is a nasty habit.

He is only smoking as an act of rebellion you bringing it up will make him stick to it longer. The only thing that would make it un-cool to do it would be if you smoked.

you have to just sit down and talk with him about what smoking is doing to your body and his life and how much money he is spending on smokes daily