A friend, a non-smoker and a climber (Kilimanjaro, Mt Blanc and many more), writes:

I sound like a 60 a day man over 4000 metres but I am prepared to believe that consistently depriving oneself of oxygen might help. You can prepare for high altitude by breathing reduced oxygen air through a mask for a few hours a day for several days. It is all to do with air pressure at the end of the day.

Update: Deadline News has the story here – Smokers could be on top of the world, claims climbing expert.

I particularly like the quote from Henry Stedman, author of Kilimanjaro: the Trekking Guide to Africa’s Highest Mountain:

“While those of my clients who’ve led a blameless, tobacco-free life frequently struggle with the altitude, long-term smokers tend to saunter up.

“Breathless, certainly, and often wheezing – but headache-free and happy. Of course, we’re not seriously suggesting you take up smoking – but it’s interesting, isn’t it?”