What evidence is there that smoking causes cancer?

Question

Im curious, we are learning about Tobacco and other legal/illegal drugs in science.

Answer 1

The nicotine in cigarette smoke causes an addiction to smoking.

Cigarette smoke is a complex mixture of chemicals produced by the burning of tobacco and the additives. The smoke contains tar, which is made up of more than 4,000 chemicals, including over 60 known to cause cancer. Some of these substances cause heart and lung diseases, and all of them can be deadly. You might be surprised to know some of the chemicals found in cigarette smoke. They include:

* cyanide
* benzene
* formaldehyde
* methanol (wood alcohol)
* acetylene (the fuel used in welding torches)
* ammonia

Cigarette smoke also contains the poisonous gases nitrogen oxide and carbon monoxide. Its main active ingredient is nicotine, an addictive drug.

Tobacco use accounts for about one third of all cancer deaths in the United States. Smoking causes almost 90% of lung cancers. Smoking also causes cancers of the larynx (voice box), oral cavity, pharynx (throat), esophagus, and bladder, and contributes to the development of cancers of the pancreas, cervix, kidney, and stomach; it is also linked to the development of some leukemias. Cigars, pipes, and spit tobacco all cause cancers, too. There is no safe way to use tobacco.-

Answer 2

Any foreign substance added to the body may have the potential to cause cancer. Truth is that everyone's body is different. A nonsmoker can get lung cancer, while a life long smoker can live to a great age and never get lung cancer.

However, smoking does cause emphysema and heart disease. Those are just as bad as cancer because the end result is an untimely and often painful death.

Most of your tobacco education will consist of persuasive arguments to keep you from smoking or to get you to quit. They'll use scare tactics, appeal to emotion, graphs and charts showing how much money the average smoker spends on tobacco products. But you just want the facts and prefer to make your own decision.

I will tell you this from experience. Smoking offers you nothing. But once you start, you end up feeling like you are missing something when you try to stop smoking. So it's kinda like becoming a smoker is like digging a hole in yourself and then filling it with cigarettes. The hole will always be there, so you will always need to keep filling it.

Is smoking cool? Yes.
Are smokers persecuted by society and treated unfairly? Yes.

Is smoking bad for you? Yes.
Will it kill you? Most likely.
Should you try smoking just to see what it's like? No.
Should you quit if you have already started? Yes, the sooner the better.

I smoked for 14 years and quit just a little over a year ago. It was a very wise choice. But remember, it should be a choice and not a law.

Answer 3

There is no such thing as an ABSOLUTELY CONCLUSIVE conclusion in science. This is particulary so when the evidence is largely epidemiological, as in the case of smoking. But keep in mind that there is no absolutely conclusive evidence that gravity causes things to fall down, either. There comes a point where the evidence for something is so overwhelming that it's almost certainly true. The evidence in the case of smoking includes studies that show that lung cancer rates track the incidence of smoking, and a laboratory studies in which animals forced to smoke or painted with tobacco tars develop cancer while control animals do not. It is *possible* that the animal studies don't apply to people and that all the people who smoke are getting cancer for some reason that doesn't have to do with smoking, but the chance is so miniscule that it isn't worth bothering with.

Answer 4

The trouble is that ethically scientests can't do an unbiased study on this. In a proper scientific study you would get a random group of people, separate them randomly into 2 groups and tell one group to smoke and the other group not to. Then you just count the cancers and compare groups.

Ethically we can't do that (we would be risking their health and also exposing them to an addictive drug) so we have to make do by looking at the instances of cancer in smokers compared to non smokers. There is a very large correlation, but some odd people will still argue that there hasn't been a scientific study on it so there is no proof.

Just be aware that there is plenty of *evidence* to say that smoking can increase cancer rates, but no *proof* and there is never likely to be because scientists cannot do the correct studies.

Answer 5

I don't know if I'm right but I thought that everyone has cancer. Not in the sense that it's killing you, but it's there and just needs something to trigger it off. How true that is, I don't know. My Grandad smoked all his life and died from old age. I have had friends die in their 20's from cancer. Even children develop cancer.

I suppose fags increases the risk of developing cancer.

I believe that because 99% of food contains either pesticides and chemicals (flavours, colouring, emulsifiers etc..) and that's what is also triggering cancer. There's definitely a link between the two, chemicals in food have risen, cases of cancer increasing year on year.

Answer 6

I have had a theory explained to me which makes sense in the most part. Stress causes all of the bad things in your body. Cancer heart attack all of that stuff. How is it that a perfectly healthy person can have a car crash for example and then develop so many disease's? Cancer etc.

Answer 7

None. My father died at 88 and smoked until the day he died. I'm 68 and have smoked a pack a day for 55 years. I'm active and healthy and a cigarette is still pure joy to me.

I get so upset with these people who scream in fear that they're going to get cancer when they smell a little smoke.

Answer 8

Do you remember a year or so ago, when they found that Sudan 5 in our foods ?
They said it DEFINITELY gave you Cancer............. but theyre not sayin nuthin about that now, only Cigarettes.
Is it cos if we knew we got cancer from that...... its the government we'd sue.

Even talkin about banning us smoking in our own cars !!!

The reason why Labour hate the Tobacco companys is cos theyve been proping up the Tori party for years.

Answer 9

we all carry the cancer gene, some of us are lucky if it does'nt activate, if it does & you smoke then that is said to be the cause, if you've never smoked, it seems that its passive smoking, so therefore smokers fault, but what does a doctor say to a patient that has never smoked & has cancer?

Answer 10

All of the people who are breathing through holes in their throats would agree that smoking causes cancer