Sleep - How much can affect your aging

Both too much and too little sleep can reduce your life expectancy (1). The optimal sleep for a long life seems to be between six and seven hours per night, according to a study of 1.1 million men and women. During the study period, the risk of death increased by 15% for those who slept eight hours, and 20% for those who slept nine hours per night. Sleeping less than four hours also significantly increases death rates

It is vital to be consistent - try to work a steady number of hours per week, and aim for the same pattern in your sleep routine as well. Maintaining consistent Circadian rhythms will insure health much more than a nine-hour night followed by a five-hour night

Of course, not everyone needs the same amount of sleep. Your body type, state of health, age, fitness, and mental state affect your individual need for sleep

(1) Kripke, Daniel, Archives of General Psychiatry, 2002, February.