Let me quote you, my friend:
"Ok, how many world champions has chess seen so far and among them how many are/were drug addicts or chain smokers or are/were mentally ill?

Excluding the world champions since 2006 because they are still pretty young, the number is 13. Among which clearly 6 match the description (I migh have missed a couple more players), so that's nealy 50%. Isn't that a pretty big percentage?"

You're switching your points each time they're challenged.
So is it 50% or 4 out of 16? Because that's 25%.

But there isn't even a strong correlation.
The number of mentally ill/drug addicts/alcoholic is completely the same in all fields.

For every insane chess champion, there are 10 who are completely normal.
For every drug addict musician, there are 50 who live completely clean.
For every alcoholic, there are 100 that would never touch a beer.

There are only about 1400 chess grandmaster in the whole world. Are they all insane, or drug addicts, or mad geniuses? Of course not. Most of them are completely normal, average guys, who enjoy watching TV or reading a book every now and then, and lead completely normal personal lives with wifes and kids.

I know it seems so romantic and mystical that geniuses must be completely insane, but it's simply not true.

There is a few nutcase every generation, but they're the exception, not the rule.

Let's not look at the 1400+ ~2500 rated grandmasters. Look at the ones who dedicated their life to chess spending more than 10 hours with it daily, the masters who created the immortal games which masters to this day consider masterpieces of the game, masters who were world champions.

A huge percentage of those world champions have ended their life in tradegy (yes ~ 50% is a very huge number), facts don't life.

Just out of curiousity, I've checked the short biographies of all chess champions, and except for the above mentioned 4, all of them lived pretty average lives.

Really? Bobby Fisher led a normal life according to you?

Fischer, Tal, Steinitz, Alekhine.
Except for these four, I haven't found anything out of the ordinary.
So where are those you talk about exactly?

Correlation is not causation. Its not that chess made people go mad but rather these people had extraordinary brains that were liable to go over the edge. Without chess it just would have been something else like maths or crossword puzzles or something.

What about Morphy?

Going to extremes has its costs be it business, sports, arts, or sciences. The idea is to strike right balance and not get carried away and become obsessed. Most players you mentioned had poor health because they did not pay attention to other necessities of life. So it is not playing a lot of chess but rather neglecting a lot of other necessary things in life that does the damage. Gary Kasparov is a glaring example who shatters your weak argument. This man is strong both mentally and physically because he chooses to remain attached with real world. One need not be a chess grandmaster to lose touch of reality, there are good number of mathematicians who go crazy. And their greater number of ordinary guys who go crazy. It is not maths, or chess, or anything else but it is their choice of becoming obsessed with a particular thing and igonore other things necessary for survival is what is responsible. Ultimately it is the person. 

If you look closely, you'll find hundreds of cases where a chess master's life has ended in tradegy, I've only considered the 6 most famous players who were all world champions.

The top 10 of today are all very young, still in their 20s. It takes time for chess to deteriorate a person's mental health by modifying the neural paths. Magnus has already started to show some signs, look at his interviews, he struggles to make complete sentences when he speaks. It's just a matter of time before he turns into the next Fisher. Kramnik is a chain smoker, he was also involved in the toiletgate scandal where it was alleged that he used a computer in the toilet.