February 2nd, 2009
12:43 PM ET

Phelps faces risks from firing up

By Danielle Dellorto
CNN Medical Producer

“What was he thinking?” That seems to be the common reaction when fans hear the news that Olympic superstar Michael Phelps got caught smoking pot. What’s interesting is, as I dug deeper, I realized people weren’t too concerned that his behavior may harm his health, but more appalled that his getting caught could cost him millions of dollars in endorsement money.

This got me thinking that a lot people look at marijuana as having very limited impact on our health. One friend made his case to me with absolute certainty in his tone, “In the big scheme of things, smoking pot is not going to hurt me.” He added, “At least I don’t smoke cigarettes.”

But is that really true? Are cigarettes worse for your health than marijuana? An overwhelming amount of research says not so fast.

Smoking one marijuana cigarette sends the same amount of tar into the lungs as four tobacco cigarettes. Turns out pot contains about 400 chemicals and 50 percent more carcinogens than a tobacco cigarette. Carcinogens cause damage to the DNA in our cells, increasing your risk for lung infections, heart disease and even cancer.

Pot is becoming as addictive as tobacco too. What’s being sold today is not your parents’ generation of marijuana. A study released last summer compared pot being smoked today with what was smoked back before 1992 and concluded it is 175 percent more potent, resulting in more frequent use and increasing it's addictive properties.

The short-term health effects probably won’t surprise you: impaired judgment, forgetfulness, difficulty focusing. But the long-term effects are physical. Marijuana smoking causes asthma, chest colds, lung infections and increased heart rate. Experts believe marijuana causes more damage to the respiratory system than cigarettes because pot smokers hold the smoke in their lungs longer than a person inhaling tobacco.

People may not realize their chronic chest cold could be the result of smoking pot and quite frankly for some people it may not even matter. But for a professional athlete, a swimmer no less, who relies on the strength of his lungs to win gold medals — the health ramifications just don’t seem worth it.

So here are my questions for you: Why is it so common for people to believe smoking pot doesn’t impact your health? Were you surprised by what you read? And don’t forget to sound off on Phelps. I want to know what YOU think he was thinking!

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soundoff (54 Responses)
  1. Yvette

    He's 23 I'm sure he wasn't thinking. Don't most 23 year olds live in the moment? Am I excusing him? No but I'm sure he wasn't thinking about his health in the long term, I'm pretty sure he was thinking more along the line of hey its a party, I'm not in training, what the hell? I sure don't think any less of the young man, I think because of cameras everywhere these days he may want to keep his pot smoking strictly private if he's gonna do it. Maybe he should make a porn(Paris Hilton) or get 5 or 6 DUIs(Lindsey Lohan) then he would just get more famous make more money and parents eveywhere could help him further his image by buying Michael Phelps everything for their kids. Paleeeze. Michael Phelps owes his mother and himself an apology. The end!

    February 10, 2009 at 23:55 | Report abuse | Reply
  2. N

    What about a vaporizer?

    The only objections I see to marijuana in this article involve smoke, not THC.

    February 12, 2009 at 14:43 | Report abuse | Reply
  3. Christopher Glenn Fichtner

    The argument that marijuana is more carcinogenic than tobacco is inferential, and not necessarily compelling. It is based in part on animal studies of questionable generalizability and in part on in vitro collection of tar from cannabis combustion; it is not based on a demonstrated relationship between smoking cannabis and the later development of cancer. In fact, the best data for answering that question do not support the argument that marijuana is carcinogenic at all, let alone more so than tobacco. The most informative data would be from the UCLA-based case control study with roughly 1200 cancer cases and 1000 controls, and the large Kaiser data base of some 65,000 individuals. Neither found marijuana use to be correlated positively with risk for developing cancer, and in fact the former study suggested that the relationship might even run in the opposite direction-numerous nonsignificant negative correlations that would be consistent with the possibility of reduced cancer risk in cannabis users. There are a number of basic science studies with animals that are consistent with that notion as well.

    Why would the above be the case, especially if there is so much more tar from a marijuana cigarette than from tobacco? Well, it is possible-this is my speculation here-that when it comes to the carcinogenicity of tars, the presence of other compounds in the chemical milieu may affect the expression of that carcinogenic potential. For example-again, this is speculative but not inconsistent with the data-THC might inhibit the potential carcinogenicity of tars (their carcinogenic effect on lung tissue or head-and-neck) while nicotine might well activate it.

    Most importantly, the best data do not support the conclusion that marijuana use is likely to lead to lung cancer. Now, research does tell us that longer term, heavy marijuana use is associated with more bronchitis, but not so much with light to moderate use. As for the issue of asthma, there may be a subset of individuals who develop asthmatic reactions to cannabis, but it is not a common effect. In fact, cannabis was used in the past as a treatment for asthma because it acts as a bronchodilator.

    Cannabis is less addictive than many other commonly used substances including alcohol, tobacco, and caffeine. What most users do when they have access to more potent cannabis (higher THC concentrations) is adjust their intake downward so that they smoke less.

    I don't know, but Michael Phelps might have been thinking, "I guess I'll have a little herb. It seems like when I use it, I'm less inclined to drink alcohol. And when I drink alcohol, I get impulsive and do stupid things like get behind the wheel of a car when I'm impaired-like the time I got the DUI when I was 19. I sure have learned my lesson about that. One or two hits from this bong and I'll be good; and I don't have to drive anywhere tonight anyway. Hey, wait, I didn't say you could take my picture... You better not post that on the internet... "

    February 15, 2009 at 02:28 | Report abuse | Reply
  4. ceh

    obviously like your website however you have to take a look at the spelling on quite a few of your posts. A number of them are rife with spelling issues and I to find it very troublesome to inform the reality then again I'll surely come again again.

    July 31, 2012 at 00:30 | Report abuse | Reply
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