No creditor calls your dorm to collect on the massive amounts of sleep lost to college students, who often prioritize studying, sports and social gatherings to getting their long lost zzzs. But what happens when a professor (who happens to be known as the "Father of Sleep Medicine") challenges his students to get out of debt?

Dr. William C. Dement, a leading authority on sleep, sleep deprivation and the diagnosis and treatment of sleep disorders, has taught at Stanford University since 1971. One of his interests is sleep debt. He explained, "Having defined sleep need and individual daily sleep requirements, sleep debt is therefore the accumulated amount of lost sleep. For example, if the average daily amount of sleep needed by an individual is eight hours, sleeping six hours a night for one week will create a sleep debt of fourteen hours. The larger the sleep debt, the stronger the tendency to fall asleep at any particular moment while we are awake."

Ever since Dr. Dement and Dr. Mary Carskadon carried out their first study on partial sleep restriction in the Stanford Summer Sleep Camp, Dr. Dement has been exhorting his students to get more sleep. He said, "I have carried out an exercise for credit in my Stanford University undergraduate course, Sleep and Dreams, which requires students to lower their sleep debt by getting as much extra sleep as possible. As expected, students who are able to obtain large amounts of extra sleep no longer feel sleepy in the daytime. But more importantly, they no longer feel tired! Furthermore, if these same students, for whatever reason, stop obtaining adequate sleep, they soon start feeling tired again."

Clearly sleep debt isn't just affecting college students. In NSF's 2005 Sleep in America poll, we found that only half of adults can say they get a good night's sleep a few nights/week or more. One-half of all respondents (50%) report feeling tired, fatigued or not up to par during wake time at least one day a week, with 17% saying this happens every day or almost every day.

Dr. Dement compares sleep debt with credit card debt (another common problem among college students). He explains, "The choice is either to live your life getting eight hours of sleep a day with a huge sleep debt, and to be tired all day long, to be impaired and dangerous, in short, to live as a zombie or to decrease your sleep debt to a very low level, and then to get your eight (or so) hours of sleep every night, and to be full of energy, wide awake, performing at your peak, and feeling optimistic and cheerful all day long. It is somewhat analogous to having a huge credit card debt and paying the bill each month with nearly all the dollars going to pay the interest on the debt. Or, to maintain a very low or zero credit card debt such that you pay only the bill each month only for goods purchased."

How do you get out of debt? It may actually be easier than getting out of credit card debt after all. Dement suggests, "Pay attention to how you feel in the daytime, keep track of how often you think you need a nap, or how often you feel tired or feel drowsy, keep track over at least several days to have a clear idea of how tired you are during the day. Try using NSF's new Sleepiness Diary for one or two weeks. Then, each night, obtain the amount of sleep you think you need."

Or if you would rather try the exercise Dement has given his students, "Start by obtaining as much extra sleep as possible. Maybe you are pretty sure you need eight hours. You know you don't need ten. Then get ten hours of sleep for a number of nights – you will reach a point where you feel wide awake and alert all day long and you will no longer be able to sleep ten hours, or even nine at night. Not having a large carryover sleep debt, you will only be able to obtain the amount of sleep that you personally need each night."

Keeping a sleep diary for one or two weeks may help you figure out how much sleep you are losing each night and how much you really need.

This article was published in the Summer 2005, Volume 7, Issue 3 of sleepmatters.