Eating sugar near bedtime can make you restless and jittery and can keep you from falling asleep. If you need a treat at bedtime, a glass of warm milk is your best bet. Alcohol and tobacco taken near bedtime can also interfere with deep sleep. It's true that a nightcap will make you sleepy, but the sleep it induces is light, restless, and shot through with periods of wakefulness. Likewise, you may associate tobacco with relaxation, but it actually increases tension.
Tobacco is a stimulant that makes the heart race and blood pressure rise.
It's best avoided altogether, but if you choose to smoke, avoiding it in the hour or two before bedtime will make your sleep more restful. If we polled farmers or anyone else who does manual labor eight to ten hours a day, very few would report a problem with insomnia. But for most of us, hard work is reserved for the mental sphere, so we need to exercise our bodies if we're going to sleep well. Doing some form of aerobic exercise at least three times a week also increases this ratio. Just be sure to avoid strenuous exercise within several hours of bedtime-it can be stimulating.