A new study shows that smoking disrupts sleep in two ways. First, as bedtime approaches, the smoker has a final "relaxing" smoke before retiring. That smoke may seem relaxing, but nicotine (the drug found in tobacco) is actually a stimulant, and smoking that cigarette is almost as sleep disrupting as drinking a cup of coffee.
But smoking disrupts sleep in yet another way. During the night, you go hours without a cigarette. This leads to discomfort and mild withdrawal, making it difficult to...

