(Image credit: Future) I recently started tracking my sleep with an Apple Watch, and it's told me something I already knew: I sleep for around six hours a night . While expert guidelines recommend that adults should sleep seven or more hours a night for optimal health, my sleep tracker consistently awards me high sleep scores. So, does this mean six hours of sleep is enough? Key takeaways: At a glance My high sleep scores from my sleep tracking device don’t mean my average sleep duration of six hours is enough — most research still supports seven hours as the minimum for long-term health. Only a very small number of people are true 'short sleepers' genetically; for most, consistently getting less than seven hours is linked to higher health risks and reduced life expectancy. Chronic sleep deprivation impacts the whole body, including cardiovascular, immune, and hormonal systems — even if you feel mentally fine in the short term.…