Nicotine was first isolated from tobacco in 1828, but was likely used in the form of tobacco long before then, from at least the days of the Mayans. The tobacco plant is native to the Americas, and although it has a long history with humanity, has caused huge numbers of deaths in that time. Nicotine is the most well-known chemical present in tobacco, and it’s also present in trace amounts in things like tomatoes and potatoes. Its close association with smoking has led to much misunderstanding regarding nicotine, and finding out the facts is important for anybody considering using nicotine replacement therapy products like patches and gums, snus or electronic cigarettes.
Nicotine is Why People Smoke
Nicotine is a drug, and it’s ultimately responsible the allure of smoking. This wasn’t known until the 1960s, when tobacco companies began to realize where the true appeal of their product lays, and was only officially recognized in the Surgeon General’s 1988 report. Dr. Murray Jarvik is one of the scientists who worked to show that nicotine was responsible for smoking, using the earlier invention of nicotine gum to alleviate cravings for cigarettes in rats. He went on to invent the nicotine patch, which is widely used (alongside gums) to help people quit smoking. It replaces the nicotine the smoker craves and therefore makes it easier to stop smoking.
Nicotine’s Effects are Related to Dopamine
Dopamine is a natural “motivator” and “reward” chemical in the brain. It’s used by the brain to encourage us to do things like eat, drink fluids, reproduce and other things like seek company. When you feel hungry, your dopamine system is being stimulated to encourage you to eat, and then when you finally get some food more dopamine is released as a reward. Nicotine can “imitate” a natural component of the system, stimulating the release of dopamine and creating a pleasurable sensation for the user. Many drugs of abuse act on the dopamine system in the same or similar ways, and dopamine is also often stimulated by addictive behaviors such as gambling.
Nicotine Can Seem Relaxing, Although it’s Actually a Stimulant
There is a paradox inherent in the effects of nicotine. It’s a stimulant drug, creating effects such as increasing heart rate, alertness and blood pressure through an increase in epinephrine, but many users report relaxing effects following a cigarette. This effect has been shown to be related to the dose of nicotine, but it’s been theorized that this is due to the dose of nicotine alleviating the withdrawal symptoms rather than a direct effect of the substance.
Nicotine is More Addictive than Alcohol, Marijuana and Cocaine
The impact nicotine has on the dopamine system makes it an addictive substance, like many illicit drugs such as cocaine. The brain effectively learns it can get a dopamine fix through nicotine, and although there is a “latency” period after the consumption of nicotine (in which the receptors are still being stimulated), when levels drop the brain begins to crave more. The individual feels agitated, drowsy, anxious and even depressed. This is why hardened smokers will often smoke their first cigarette within five minutes of waking up, because their levels of nicotine have decreased overnight and they begin to feel withdrawal symptoms, so they need to increase their dopamine levels to alleviate them. The need to smoke is even greater than the need to eat breakfast. When the difficulty users have in quitting various substances is compared, nicotine is more addictive than alcohol, marijuana and cocaine.
Nicotine Was Used as an Insecticide
Nicotine is toxic, and that fact drove its use as an insecticide, which first started in 1763. Sprayed onto a plant, it will kill many insects that come into contact with it, because it is absorbed into the body like it is in humans when used as a nicotine patch. This is also assumed to be one of the chemical’s natural functions, and gardeners have exploited it for centuries. However, this is no longer allowed in the U.S., due to nicotine’s toxic effects to many mammals.
Nicotine Doesn’t Cause Cancer
Smoking undoubtedly causes various cancers, and for this reason many people assume nicotine itself is carcinogenic. This has been investigated many times in research, and the general consensus is that nicotine doesn’t cause cancer. One example piece of research involved exposing rates to vaporized nicotine for 20 hours a day, five days a week over the course of two years, exposed to twice as much as a heavy smoker. The rats exposed to nicotine didn’t die more frequently than those not exposed, and they were no more likely to develop tumors.
Research looking at cancer risk associated with nicotine replacement therapy compared to that for smoking has found a link for smoking – as is expected – but no risk from use of patches and gums. In addition, smokeless tobacco (such as Swedish “snus”) contains nicotine (as well as carcinogens), and the majority of research on the topic has found no increase in cancer risk (at least from modern products). There are around 70 carcinogens in tobacco smoke, but nicotine isn’t one of them.
Nicotine Doesn’t Cause Cardiovascular Disease
Smoking is a well-known cause of cardiovascular disease, and this has led many people to assume that nicotine has a role to play. Some evidence for this hypothesis has been provided in animal studies and in cell cultures, showing that nicotine has several effects that could deem it a risk factor for cardiovascular disease, but research on humans hasn’t observed this effect. In a meta-analysis looking at data from 35 clinical trials comparing nicotine patches to a placebo, the researchers found no correlation between nicotine patch use and cardiovascular effects such as heart attacks, strokes, angina and a rapid or irregular heartbeat, with these outcomes being just as common in the participants not receiving nicotine. There are transient effects of nicotine on the cardiovascular system, but these disappear when individuals stop consuming nicotine, and may be less pronounced in long-term nicotine users.
Nicotine Improves Memory and Alertness
There are also positive effects of nicotine, and this includes some minor effects on brain function. This effect is related to its stimulant nature, and has been confirmed to take place in smokers (whether previously deprived of nicotine or not), ex-smokers and non-smokers. A meta-analysis of 41 pieces of research on the topic found that it had a significant effect on many different areas, including fine motor skills, attention (both focusing on important things and ignoring irrelevant ones), short-term memory, working memory and response time. This explains one of the reasons smokers find it challenging to go without nicotine; they miss the stimulation.
Nicotine Could Help with Cognitive Impairment and Protect Against Parkinson’s
The stimulant effects of nicotine can help people suffering from mild cognitive impairment, which is a symptom of Alzheimer’s disease and several types of dementia, according to the results of a 2012 clinical trial. Non-smoking participants with the condition assigned to receive nicotine patches showed improvements in their cognitive performance (as measured by a test), as well as in attention and memory. There is also evidence that cigarette smoking halves the risk of Parkinson’s disease, and research on rats has showed that nicotine protects the key brain region affected by the condition.
Nicotine isn’t as Toxic as You Think
Many sources of information claim that the toxic dose for nicotine for an adult is around 60 mg, but this information has recently been called into question. Bernd Mayer investigated the source of this information, and eventually found that it came from some sketchy self-experiments from the 19th century. He presents evidence of people consuming much more than 60 mg and surviving, and the much higher quantities found in the blood of people who have overdosed on nicotine. The paper suggests that the lethal dose is actually more likely to be anything from 500 mg to 1000 mg, around 10 to 20 times more than is currently assumed. Nicotine is not more toxic than arsenic.
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