There are three answers:
Stephen LaBerge and Paul Tholey had a discussion posted on the internet around destroying the dream body whilst lucid. Paul Tholey described how he was able to cut his dream body, without physical effect, and was able to split his dream body in two - right down the centre. Also he stated that on a number of occasions he experimented with ‘free-form’ ego states, or destroying the body to allow an altered sense of self perception.
You won’t die if you destroy your dream body, but you’re bound to see interesting results 
Yup, the idea of dying in real life as a result of a dream death is completely false. I’ve died in NDs before, without any sort of real-life effects–except for a sense of confusion.
Wow thanks for the answer, apart from in the study by LaBerge et al have you tried to kill your dream bodies?
I haven’t tried to kill mine, either in ND’s or LD’s, but I have died in my ND before. I just drifted off the ground and floated a dozen metres in the air.
As this assumption is false, if you force yourself to die in a LD, nothing happens IRL.
You can find a long thread about this assumption here: If you die in a dream, do you die IRL?
If you die in your dream, you have a high chance of dying IRL. It happened to me. I’m dead. The only reason I’m here posting this now is because… I’m a zombie.
:twisted: Braaaiiins!!
But seriously, problably the only way a dream could cause death is if you have an extremely weak heart, and your dream is so intense that you die of cardiac arrest. What are the odds of that, 100000000000:1?
You know, you aren’t our first zombie. But anyway, yes, the odds must be ridiculously low.
I had died in a ND. I fell of a cliff and woke up. Interesting feeling by the way. 
To die in LD, don’t believe it, but what about those OOBE?
(Out Of Body Experince)
I died in a Lucid Dream, I jumped from a building and wanted to start flying before I hit the ground, but it didn’t work and I woke up. If we could really die from dying(spelling?) in a dream the world would be a very empty place.
death will find us, may it be here, sitting at the computer, or far beyond, in the deepest dream.
who else will live to tell us that one cannot die dreaming, besides one or another who awakes at the sight of the reaper?
Well, i think that if you KNOW (not belive in, or want, or even imagine)that killing in LD will cause your death IRL, you might die IRL =] But i dont wanna try it, even if chanses are 100000000000:1 .
What will happen if ill die in my lucid dream? (never had lucid dreams yet)
Hey Zaba, welcome. 
There’s been several discussions about it here on ld4all, check these topics out:
https://community.ld4all.com/t/dying-in-a-ld/22016
^^^ The original topic has been merged into this one now 
[If you die in your dream do you die in real life?)
I think dying in an LD might be cool, maybe you’ll turn into a spirit or something (all in the dream, of course) . IRL, nothing happens… except for maybe you wake up.
Yup, many people have wondered about this. Nothing to fear. In fact, I came very close to dying in a dream last night. In another dream a few years ago, I actually did die. In both of those experiences, I just woke up after experiencing death for a moment. (Both of these dreams were NDs.)
Its fun dying in dreams. In fact, I look forward to it 
LOL! I’m glad I’m not the only one. For a while there I was starting to get worried. 
I may die in my regular dreams but have never died in a LD. When something happens that would usually cause death, since i know it’s a dream, nothing happens. 
In one book I read the reason why we call it “falling” asleep is because when you first fall asleep or you wake up, is actually similar to a feeling of falling. Which is why we often fall and wake up before we hit the ground. That sensation is actually what it feels like to fall asleep.
Just an interesting thought anyways 
A very interesting thought, but keep in mind that people can also fall victim to a trap or fall in love. Granted, some equate falling in love with the actual feeling of falling, but there is still one pesky thing: When you think of falling asleep and when you remember falling asleep or waking up, do you think of or remember the feeling of falling vividly enough to name the action of falling asleep after the feeling? Do you remember the feeling of falling at all? I don’t really think of falling at all. (But that’s just me, maybe).