Does Nicotine Cause Cancer?

Does Nicotine Cause Cancer?

Nicotine is a powerful alkaloid that is present in the nightshade family of plants. It is known to be a very addictive stimulant drug that is found mostly in cigarettes and tobacco and also other products like nicotine patches and nicotine gum.

There are so many headlines on the internet that talk about nicotine and try to answer the question of whether or not nicotine causes cancer. Some of these headlines are not entirely true and some others are grounded in truth. The effects of nicotine on the body are mostly cumulative so it doesn’t matter the level of nicotine found in a cigarette or a nicotine gum, the damage from nicotine consumption adds up over time. The more nicotine you consume and the longer you consume it, the more likely you will be affected.

Nicotine Side Effects

There are several side effects of nicotine, some of them are severe (seizures, irregular heartbeat) and some of them are common (sneezing, coughing, headaches, watery eyes etc.). The possibly fatal effect of nicotine, which is lung cancer, is still very much being investigated. What is known for sure is that nicotine is very addictive and it is a principal constituent of cigarettes and tobacco which have in them so many carcinogenic compounds that contribute to lung cancer.

The Possible Role of Nicotine in Cancer Development

Questions that often arise are whether or not nicotine causes cancer and many experts have weighed in on this matter with various professional opinions. On the surface of it, one can say nicotine is not directly responsible for cancer and might be instead indirectly involved.

When you have a mixture of nicotine and various other known carcinogenic compounds burnt and smoked in cigarettes, one can say that nicotine indirectly contributes to cancer as it is the constituent that makes it so addictive. But when it is in a little bit more isolation, like in nicotine gums or nicotine patches, for instance, it is difficult to see the link between nicotine and cancer.

However, some new researches seem to suggest that nicotine does, in fact, contribute to cancer growth. There is a list of cancers that have been discovered to have a direct correlation to nicotine and one of them is lung carcinoma. It has been shown that nicotine does possess mutagenic and tumor promoting elements and it can disrupt metabolic processes and facilitate growth and spread of transformed cells. Whether or not this research is true, it fails to show that nicotine can be directly responsible for cancer.

There is also some evidence to suggest that certain individuals have unique gene encoding that makes them more susceptible to the pathobiological effects of nicotine. These new emerging information about the carcinogenic mechanisms of nicotine are very important to note and they have steered regulation in some ways. Nicotine is now a confirmed risk factor and it has been shown to alter gene expression in cells and tissue upon exposure and with this disruption comes an imbalance in the phenotypes which are responsible for protein synthesis that control cell shape. Regulation of gene expression is very critical to any organism’s development and if this process is hijacked in any way, shape or form, cancer is a possible outcome.

However cigarette smoke contains a lot of chemicals and this makes it very difficult to isolate the toxicology relevant to the pathogenesis of smoking. Most carcinogens (cancer causing substances) are strong mutagens and they are responsible for activation of proto-oncogenes or inactivation of tumor suppressing genes. Nicotine is not considered a full carcinogen because by itself nicotine fails to induce tumor formation in experimental animals. However, an interconnection of nicotine and various other substances is another story entirely. There is also evidence to suggest that nicotine and its metabolites may play critical roles in these processes by acting as a mutagenic and immunosuppressant agent.


It would appear that evidence that nicotine by itself causes cancer is slim at best. However, it is precisely because of nicotine addiction that people smoke or chew tobacco products and it is this smoking or direct tobacco consumption that pose a cancer risk. Smoking exposes the smoker to thousands of carcinogenic compounds.

Asides from smoking, tobacco itself contains about 70 known cancer-causing substances but evidence suggests that nicotine is not one of them even though it is the primary addictive component and can be fatal in high doses. This means that nicotine replacement therapies that include things like nicotine gums and nicotine patches do not cause cancer.

Finally, it can be said quite confidently that nicotine does not cause cancer as it fails to, by itself, initiate cancer formation.