Would it be OK for a Mormon to buy cigarettes for someone else?
Mormons believe that smoking tabacco shows disrespect to our bodies, and is a violation of God's commandments regarding health. So, a Mormon buying cigarettes for someone else would have to have a very good reason for doing so.
Otherwise, buying cigarettes for someone shows that a Church member may not be as close to God as they should. This is possible because it is up to all of us, individually, to educate ourselves. The LDS gospel is extremely personal. We decide how close to God we wish to be. However, helping others defile their bodies may push us farther away from God and the gifts we receive from Him.
If your family member wants you to buy them cigarettes
If you are a Mormon and are feeling pressured to buy cigarettes for someone else in your family, please think deeply about the situation. Is there a way to change the situation while expressing love for your family member? You can also freely discuss the situation with your LDS bishop without worrying about getting into trouble.
If a friend wants you to buy them cigarettes
If a friend wants you to buy them cigarettes, and they know you are Mormon, chances are they already feel a bit bad about it. But you never know--they might even be trying to be mean. So please, communicate your thoughts about it to them and see where it goes. It is unhealthy to continually let yourself be pressured into breaking your own moral code.
If a friend wants you to buy them cigarettes, and they do not know you are Mormon, please think about telling them that you are a Mormon. You may have hesitated in the past, but it's never too late to say, "you know, I was thinking about this. It makes me uncomfortable but you've been a really good friend. Can we come up with a way around this?"
God wants you to use your mind and heart to come up with creative solutions to problems that stand in your way. We may never be perfect at dealing with our troubles, but just trying to do our best is part of learning what it means to "overcome the world."