The substance is produced in the roots of a shadow plant and stored in the leaves. Nicotine is mainly harvested from the tobacco plant as it makes around 3% of its dry weight. The plants which produce it come under the night shade family of plants. Nicotine was also used as a pesticide in the past. Today, it is popular as one of the main ingredients in cigarette, facing much criticism from concerned segments of the society.
The nicotine content in an average cigarette is 1 mg. In this small quantity, it acts an stimulant, giving a pleasing effect. At such low quantity nicotine is not harmful for health. It is not even carcinogenic i.e. does not contribute to any cancerous activity. However, as the cigarette toll builds up and the nicotine accumulates, the substance become dangerous for health and consuming a quantity above 30 mg can prove fatal.
Nicotine addiction has been described as the hardest to break by the American Heart Association. It is five to ten times more addictive than morphine and cocaine. The droplets of nicotine enter the blood stream through the smoke and reaches the brain in less than 10 seconds. It reaches all other parts within 30 seconds after which it leaves the body. The craving for another smoke starts just then when the body is deprived of the nicotine supply. This is why it is hard for cigarette addicts to quit. When a person quits, he faces nicotine withdrawal effects which may consist of symptoms like nauseas, headache, irritation and cigarette cravings.
Apart from the addiction, nicotine presence in the blood increases insulin production and the sugar level surges. A person may start feeling nausea, sweating and even tremors in severe cases. Initially, it stimulates the senses. Later on it leads to anxiety and low heart rate.