Aggressive marketing strategies, as well as misleading claims by manufacturers, have largely contributed to the belief that nicotine is fairly harmless. However, evidence shows that nicotine is far from innocuous, even on its own. In fact, a myriad of studies has described its adverse effects on cardiovascular and respiratory health, various cancers, and brain maturation.
Nicotine is naturally present, in infinitesimal concentrations, in several edible plants of the nightshade family, which includes tomatoes, eggplants, and potatoes. However, one would need to consume several hundreds of potatoes to match the nicotine concentrations found in a single cigarette.