There are by now some quite extensive studies about the amount of required or healthy sleep.
Sleep is roughly normal distributed between 5 and 9 hours and for some of those getting 5 or less hours of sleep this appears to be healthy:
Jane E. Ferrie, Martin J. Shipley, Francesco P. Cappuccio, Eric Brunner, Michelle A. Miller, Meena Kumari, Michael G. Marmot: A Prospective Study of Change in Sleep Duration: Associations with Mortality in the Whitehall II Cohort.
So probably Dave Asprey is one of those 1% for this is correct.
Some improvements (or changes) may be possible for most of us though. You can get along with less sleep if you sleep at your optimum sleep time (which differs depending on your genes esp. the Period 3 gene) and if you start to sleep quickly.
Polyphasic sleep may significantly reduce your sleep total but nobody seems to be able what the health effects are. It might be that it risks your long time health.
There are by now some quite extensive studies about the amount of required or healthy sleep. Sleep is roughly normal distributed between 5 and 9 hours and for some of those getting 5 or less hours of sleep this appears to be healthy:
Jane E. Ferrie, Martin J. Shipley, Francesco P. Cappuccio, Eric Brunner, Michelle A. Miller, Meena Kumari, Michael G. Marmot: A Prospective Study of Change in Sleep Duration: Associations with Mortality in the Whitehall II Cohort.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2276139/pdf/aasm.30.12.1659.pdf
So probably Dave Asprey is one of those 1% for this is correct.
Some improvements (or changes) may be possible for most of us though. You can get along with less sleep if you sleep at your optimum sleep time (which differs depending on your genes esp. the Period 3 gene) and if you start to sleep quickly.
Polyphasic sleep may significantly reduce your sleep total but nobody seems to be able what the health effects are. It might be that it risks your long time health.