Sleep: A to Zzzzzzzzzz 23. June 2009 William Davis (5) Take a look at the results from the Heart Scan Blog's most recent reader poll (399 respondents):How many hours do you sleep per night (on average)? 9 or more hours per night 15 (3.7%) 8-9 hours per night 72 (18%) 7-8 hours per night 152 (38.1%) 6-7 hours per night 111 (27.8%) 5-6 hours per night 38 (9.5%) Less than 5 hours per night 11 (2.8%)Like many issues in health, too much or too little of a good thing can present undesirable consequences. Too much sleep: While psychologists and sleep researchers advise us that at least 9 hours are required to fully eliminate sleep "debt" and achieve optimal vigilance and mental performance, epidemiologic studies have shown increased mortality with this quantity of sleep. Too little sleep: Getting less than 7 hours habituallly increases blood sugar, appetite, inflammatory measures, and encourages weight gain. Mortality is also increased, just as with sleeping too much. It is also associated with increased likelihood of a positive heart scan score. 7-8 hours per night from a health viewpoint is that Goldlilocks "just right" value: just enough to not erode mental performance substantially, but not so little that inflammatory, insulin-disrupting, and appetite-increasing effects develop. Of our 399 respondents in the poll, 56.1% (38% + 18%) slept what appears to be an optimal amount for health. While only 3.7% slept too much (9 hours or more), the remaining 40.1% slept too little. Our informal poll confirms what most of us observe in everyday life: The majority of people shortchange sleep in order to meet the demands of their high-pressure, squeeze-as-much-as-possible-into-every-day lives. But not paying off your sleep "debt" is like not paying the mortgage for a couple of months. You wouldn't expect your friendly neighborhood bank to say, "Oh, you forgot to pay your mortgage? Forget about it. Just pay next month's." Sure, fat chance. But if you don't pay off your sleep "debt," you will pay it back with health.