You Will Start to Feel Very Sleepy...(regular and ample sleep important as food and exercise)(Excerpt)

Adapted from "Improving Sleep," published by Harvard Medical School. For information on sleep, go to health.harvard.edu/NEWSWEEK.

We don't need a scientist or a study to tell us that there's a price to be paid for losing sleep. You sag after lunch, or just plain feel crummy. Remember when your parents shooed you to bed with "Because you need your sleep, that's why!"? They were right--more than they knew.

Research now suggests that regular, ample sleep is one of those indispensables, ranking right up there with eating right and exercising. Recent experiments show that when you shortchange sleep, the human immune system produces fewer infection-fighting antibodies, making you vulnerable to disease. Researchers at the University of Chicago studied volunteers who slept four hours a night for six straight days. They found hormonal and metabolic systems in disarray. The conclusion: chronic sleep loss might hasten the onset and increase the severity of diabetes, high blood pressure and obesity. Another study linked lack of sleep to increased risk of heart attack.

There are also benefits to the brain. In Canada, researchers used a logic game called Wff N' Proof to test sleep's influence on "complex cognitive procedural" thinking. If people get drunk shortly before going to bed, after they learn the game in the afternoon, they do 40 percent worse the next time they play it than those who stayed sober. One explanation is that alcohol suppresses the REM (rapid eye movement) cycle of sleep, which you need in order to learn well. Similar experiments at Harvard have shown that people score better on memory tests if they sleep soundly for six hours the night after learning the task.

Memories are created ...