8Smoking
When you smoke, nicotine in tobacco products can penetrate the bloodstream. This stimulant can also be absorbed through the skin when you wear a nicotine patch or the mouth when you chew it. Once in the blood, nicotine will travel to the brain in which it can activate and bind to cholinergic receptors. Those receptors are often bound by acetylcholine to maintain movement, alertness, and heart rate. Nicotine binding would stimulate your muscle movements and lead to muscle twitching. So, if you are a heavy smoker and often experience muscle spasms, try to quit smoking to reduce the risk. [8]
