One of the underlying themes interweaving among the various pieces I write is the importance of deciding upon matters or courses of action informed by evidence. This does not mean we should all be Spock to be ruled only by logic. Our emotional life is very much a rich part of what it means to be human. But it does mean, in my opinion, that when faced with alternative choices, evidence based critical thinking is often a more reliable tool than gut feelings. In examining habits or hobbies, it is possible to weigh advantages and disadvantages, and based on the evidence, decide whether or not to continue or start said habit. For example, I run, and there are disadvantages and advantages. It certainly does eat a lot of time and may, in the long run, be hard on the joints. But the cardiovascular fitness achieved, I think, outweighs those disadvantages. I also enjoy a glass (or more) of wine or beer on occasion. The disadvantages are well known, impaired ability on drinking too much, liver problems, being a diuretic, etc. On the other hand, there are health benefits if drunk in moderation.
So, what about smoking? I certainly do have some anecdotal evidence here. Three colleagues have had fathers pass away in their mid sixties due to lung cancer. All three were heavy smokers. An ex-chain smoking relative in her sixties recently passed away with a combination of lung, esophageal, and mouth cancer. But what does the science tell us?
Surprising for its time, one of the original studies from the 1950’s found a link between lung cancer and smoking. It is mentioned in this article from the BBC. The article also mentions how the push to decrease smoking in the U.K. has driven down lung cancer by 50%. In total, deaths due to lung cancer are about 1.3 million per year, with a significant portion of that due to smoking.
But lung cancer is only one of a plethora of potential risks facing smokers. The picture at the beginning of this post,
stolen borrowed from the Denialism Blog shows a smoker’s lung who suffered from emphysema. Breathlessness, fatigue, and weakness are what this person likely suffered from. From the article:
Emphysema involves irreversible destruction of lung tissue. The lung’s primary duty is gas exchange, and gas exchange is dependent on surface area. Lungs aren’t all that big. If they were simple sacs, their effective surface area would be in the range of a few square feet. The lungs create surface area by having millions of small sacs called “alveoli”, which provide about 100 m2 of active surface area (about a tennis court’s-worth).
The scary thing about this picture of a lung isn’t the black carbon deposits, it’s the large holes containing the black carbon deposits. The alveoli that used to occupy those spaces have broken down, creating large, rather than small sacs, reducing effective surface area significantly. Less surface area = less gas exchange = feeling like you can’t breath—because you can’t. About a third of smoking related deaths are caused by lung diseases such as emphysema. Yuck.
Another study shows a correlation between breast cancer and smoking in women. Second hand smoke has even been linked to an increase in arrhythmia susceptibility in a mice study. . There is a known correlation between many cardiovascular diseases and smoking. It reduces HDL or the good cholesterol. It increases the risk of stroke. Exposure to tobacco smoke has been linked to behavioral problems in boys. It damages the piping system that carries our blood. It has been found to induce remodeling changes to the heart in mice. It seems the more we learn about tobacco smoke, the worse it gets.
Cigaratte smoke contains about 60 known carcinogens, including radioisotopes from the radon decay sequence, which, of course, eventually radioactively decays down the chain via cell damaging alpha decay (and other types of radioactive decays) into lead. From the smoking section of Wikipedia, we see that it also contains nitrosamine and benzopyrene. Nitrosamine is a carcinogen and benzopyrene is known to be highly carcinogenic. Cigarette smoke also contains cyanide, formaldehyde, methanol, among more. More about smoking can be found at the Wikipedia article.
In addition to all that fun, smoker’s share all those risks via second hand smoke with anybody who happens to be around, whether or not they want to participate in those risks.
What about the benefits? It may be surprising to learn that smoking may help to delay the onset of Parkinson’s disease. Of course, that is only a delay and, unless there is a family history, it is statistically unlikely to be about to get this dread disease. In any case, I doubt very many smokers started smoking to have this benefit. Some smokers do state that smoking helps them to relax and think more clearly. As there are a multitude of alternative means to achieve those results, that’s not really a viable justification either. With the unlikely exception stated, there’s really no benefit to taking up smoking. Contrast that with all the risks, and it seems to me that a rational answer is unambiguous. It is acceptable to take risks to achieve rewards, but there simply is no reward here.
With the evidence before us, there is simply no way to provide an evidence based rationalization to begin or to keep smoking. I understand it may be hard to quit for some, but to not at least even think about quitting or making the effort is not rational.
If I may be permitted to rant a little, smoking also makes food taste like crap. Nothing is worse than when I am enjoying a meal outside and somebody walks by smoking. It is also extremely annoying when smokers flick ashes and throw cigarette butts out of car windows or wherever they happen to be standing. Is the entire world simply an ashtray to them? Inconsiderate behavior such as this is one of the many reasons many are viewing smoking as socially unacceptable.
So, now that I’ve written the definitive post on smoking, I expect that all smokers everywhere will give up the habit, and I’ll be able to get into a Las Vegas show without having to plow through a nasty toxic cloud of tobacco smoke.