I had every intention to write a column about holiday gift-giving that focused on non-toxic skin care (such as Rosy Glow Skin Care in Ashland, and others: ask a practitioner about purity before you book an appointment!) and stress reduction (massage? Hot tub soaking at Chozu Gardens) and detoxification (Cure Infrared Sauna in Medford.) And then I read an article describing the extent to which sleep loss is still an issue, and I just have to go there. A good sleep habit is the best gift you can give yourself this winter. Long dark nights are the perfect season to perfect the art of deep and restful sleep!

Sleep seems like a crazy thing to do: imagine our primitive ancestors, completely lacking electronic surveillance to detect approaching predators. Why on earth did the ones who nodded out at night live to reproduce (our ancestors) while the insomniacs (if they ever existed) died out? Every species on earth sleeps, but why? Sleep is only vital for the short and long term health of your brain, emotional health and impulse control, immune system function, and—for the younger folks among us—normal growth and development. If you can kiss all of that goodbye, you needn’t keep reading.

For those of us who value our mental and physical health, we should be clocking in (without looking at the clock) about 7.5 hours nightly, if you’re already well-rested and in the groove. If you are ever sleep challenged, it’d be best to aim for 8-9 hours. You have a “sleep debt” which you can definitely sleep your way out of, though the path to “enough” is not a clear one. If you have a sleep debt to make up, naps are a good way to go: 20-40 minutes before 3 p.m. if you can manage it. (Prominent employers such as Google offer sleep pods to improve worker health and efficiency!) Night-time catch up is problematic: it’s hard to go to sleep early (but do it if you can) and sleeping late in the morning compromises the next night’s sleep if it’s more than 30 minutes. Best to never get behind.

Which would put you in the minority: our average in the US is under seven hours, which is not okay in anyone’s book, despite boasts to the contrary. No individual has ever been proven to maintain optimal health with shortened sleep, though many claim to be sleep wizards. What does seem true as many claim is the variety of chronotypes: I am indeed an early bird, well-suited to farming and rowing—I’ll take that one, and others indeed are night owls and well-suited to careers in the theater. High schools of course, don’t distinguish very well, but again—forward thinking companies like Nike do have flexible work schedules.

Evaluating the quality of your sleep can be both subjective (you know when you’ve slept well) and objective: sleep tracking devices are actually helpful. Well shy of a good night of sleep are many forms of a bad night: literally tossing and turning all night is rare. Far more commonly people feel as if they haven’t sleep but in reality they are uncommonly still for hours at a time (just try and hold still for three hours), suggesting that they are in lighter stages of sleep. Better than awake but not fully restorative.

If you do choose to use a sleep-tracking app on your smart phone, be sure to put the phone on airplane mode: keeping wi-fi as well as televisions and other significant electronics out of the bedroom are key to getting a good night’s sleep. If you are a shallow sleeper, you are easily awakened, and not fully rested. There are many supplements, therapies and strategies to deepen your sleep, all of which fall into the category of “sleep hygiene.”

The first and most important step of sleep hygiene, and indeed of achieving any improvement in your mental or physical or emotional health is to prioritize sleep. So for your big holiday gift this year, decide whether you can confidently claim good sleep and settle for 7.5 hours, or whether you have a big of sleep debt: go big! Aim for 8-9 hours of sleep on a regular basis and enjoy your winter darkness and healthier next year!