Nicotine is the well-known addictive substance found in cigarettes and a range of other tobacco products, as well as in most brands of e-cigarettes (electronic cigarettes). Previous evidence has shown that long-term exposure to this substance can cause abnormal tissue thinning in the part of the brain responsible for many essential conscious thought processes. In a study published in March 2014 in the journal Neuropsychopharmacology, researchers from three U.S. institutions investigated the potential of nicotine exposure to produce brain thinning in young adult smokers and teen smokers. These researchers found evidence of brain thinning in the study participants and linked this thinning to the presence of nicotine addiction.
The Basics Of Teens And Smoking
According to figures compiled through an annual federal project called the National Survey on Drug Use and Health, young adult Americans in the age range between 18 and 34 smoke cigarettes more often than any younger or older segment of the population. The peak smoking rate (34.1 percent in the average month) occurs among people between the ages of 21 and 25. Slightly lower rates of monthly smoking (ranging from 33.4 percent to 31.9 percent) occur among people between the ages of 26 and 34. Among people between the ages of 18 and 20, the monthly smoking rate is 28.2 percent. All of these rates are substantially higher than the estimated smoking rate of 19 percent among all U.S. adults.
Smoking rates are important because most people who smoke will eventually develop a nicotine addiction. Nicotine has the potential to produce addiction because it makes changes in normal brain chemistry that lead to increased feelings of pleasure in users. Critically, the pleasure from nicotine exposure only lasts for a very short period of time; this means that smokers have a very strong incentive to keep smoking and supplying their brains with more and more of the drug. Ultimately, repeated exposure to nicotine leads to long-term changes in brain chemistry and the onset of physical nicotine dependence. In turn, this physical dependence is commonly accompanied by symptoms of addiction such as repeated cravings for more nicotine intake, an inability to effectively limit nicotine intake, withdrawal symptoms in the absence of expected nicotine intake and continued participation in nicotine use despite clear knowledge of the dire health consequences associated with smoking.
Does Smoking Really Thin The Brain?
Most of the well-established physical harms of smoking come from exposure to the vast array of disease-causing chemicals found in commercially grown tobacco, not from exposure to nicotine. However, current research shows that repeated nicotine exposure also produces a significant impact by abnormally thinning tissue in the part of the brain responsible for executive function, a term that scientists use to describe the ability to do such things as think logically, make and recall memories, learn from past behavior and make appropriate judgments and decisions. In the study published in Neuropsychopharmacology, the American research team used an examination of the brains of 42 people between the ages of 16 and 21 to determine if the brain thinning found in older smokers also occurs in smoking teenagers and young adults. Eighteen of these participants had an established history of cigarette use; the remaining 24 did not smoke.
After comparing the two groups, the researchers concluded that, on the whole, there were no clear differences in brain thickness between the teens and young adults who smoked and the teens and young adults who didn’t smoke. However, when they made comparisons within the smoking group, the researchers did find evidence of substantial differences in brain thickness between those individuals who had smoked relatively few cigarettes and those individuals who had smoked a relatively large number of cigarettes. Specifically, the fairly light smokers had more or less normal brain thickness in the examined region, while the fairly heavy smokers had signs of abnormal thinness in this region. In addition, those smokers who were nicotine-dependent and also showed signs of nicotine addiction had more signs of brain thinning than their non-dependent, non-addicted smoking counterparts.
The authors of the study published in Neuropsychopharmacology note that their findings do not prove that nicotine exposure leads to brain thinning in teens and young adults. However, they also note that the correlation between brain thinning and relatively heavy cigarette use does indicate that the level of exposure to nicotine is a critical factor in the abnormal thinning process. In addition, the study’s authors note that nicotine dependence, nicotine addiction and structural damage in the brain may have overlapping relationships throughout a smoker’s lifetime history of cigarette use.
Read More About Tobacco – A Gateway To Marijuana?