Sleep Debt Difficult to Pay Back

We often hear that the world is increasingly focused on efficiency, convenience and productivity and ultimately functions on a 24/7 basis.  Sleep studies support this idea, finding that as a whole, we sleep less than we did 25 years ago – about one hour less per night. Yet this one hour of wakefulness gained does not necessarily lead to higher productivity, and may in fact hinder our performance. The problem is that sleep debt is slowly building up and impairing energy, mood, and cognition.

“Sleep debt” refers to the accumulation of lost sleep over time. The concept of sleep debt is simply a matter of balance: the amount of sleep lost equals the amount that must be gained in order to avoid potential consequences. However, as sleep debt grows larger, it becomes very difficult, if not impossible to pay back, and normally cannot be recovered in a weekend sleep-in. As a biological need, seven to nine hours of sleep each night should suffice for the average adult. However, many people fall short of this mark, with approximately 30% of adults getting only six hours or less each night. As National Geographic states: We are “racking up huge sleep debt!”

Boston’s Brigham and Women’s Hospital recently completed a study seeking to determine the effects of sleep debt on the brain. Using volunteers who stayed awake for 33-hour stretches with 10-hour sleeps in-between (equal to about 5.6 hours in a 24-hour period), the study measured their cognitive and motor skills every few waking hours. The researchers found some interesting observations: Alertness always declined throughout the day, despite feelings of rejuvenation upon waking; and the extent of this decline in alertness grew larger as the study wore on. The findings suggest that sleep loss affects the brain by building up over normal waking hours, and also by accumulating over days or weeks. A well-rested person should be able to recover from an occasional all-nighter fairly easily.  However, when someone with acquired sleep debt pulls an all-nighter, the negative effects of sleep loss multiply.

Taking on too much sleep debt can result in consequences ranging from workplace errors and lost productivity, to fatal accidents and the emergence of health problems including obesity and hypertension. Sleep debt can also cause illnesses as it weakens the immune system and heightens susceptibility to viruses such as the common cold. In addition, people with sleep debt are more likely to develop sleep disorders including insomnia and restless legs syndrome. Essentially,  as debt grows, so do physical and cognitive risks.

Is sleep simply not a priority in our 24/7 world? There are important health and safety implications of sleep debt that call for careful consideration of the value we place on sleep, especially for those who work long hours or shift-work.  Together with diet and exercise, sleep makes a vital contribution to overall well-being. Don’t let yourself get too far in debt.