Sleep is a funny and sometimes elusive thing, isn’t it? We want it when we can’t have it and often when we’re supposed to be winding down and getting some, we find ourselves wide awake flipping through Netflix, doing everything we can to avoid it altogether.

Sleep can affect both your mental and physical health, with better brain function, muscle recovery, hormone balance, longevity, and even fat burning reliant on your quality or quantity of rest, but at least approximately four out of every five people wrestle with occasional insomnia.

“I think sleep is honestly one of the greatest biohacks and the biggest performance-enhancing thing that you can do,” says sleep expert and Oura Ring creator Harpreet Rai. “Sleep is the foundation of our health and the foundation of our body and mind.”

After about 19 hours without sleep, your brain starts to function significantly slower. Your reaction time, attention, memory, and mental accuracy all drop significantly — the equivalent of having a blood alcohol concentration of 0.05 percent. Round it out to a full 24 hours without sleep and that brain function is on par with somebody who is legally drunk with a 0.08 BAC. This is because while you’re sleeping, your brain is busy cleaning away and flushing out cellular waste, prepping you for quicker mental processing and even a better mood.

As for the rest of your body, muscles recover and fat is burned while you’re asleep. Testosterone and growth hormone levels drop, impairing your protein synthesis so you struggle to build more muscle when you get poor sleep or inconsistent sleep. When cortisol levels rise, fat storage rises as well and muscle mass starts to break down.

And of course, sleep aids in the aging process and the lack of it will certainly speed aging up. Simply getting consistent sleep in complete darkness as opposed to partial darkness (i.e. thin blinds or sleeping near lights vs installing blackout curtains) can decrease your risks of developing cancer by 200 percent in your lifetime. Researchers believe this happens from something as simple as your body producing less melatonin when exposed to light in the evening, and therefore significantly impacting your quality of sleep. Meanwhile, getting less than six hours of sleep a night doubles your risk of heart attack and increases risks of diabetes by 25%. And overall, these numbers add up to a total 25 percent increase in your risk of early death if you suffer from (or put yourself through) consistent sleep deprivation.

But of course, it’s important to remember sleep quantity is not the name of the game when compared to sleep quality. Getting at least six to seven hours of consistent, quality sleep is sufficient for most people and if you’re physically active (working out at the gym, playing sports), getting the occasional seven to nine hours is recommended to allow your muscles proper recovery time.

So treat good sleep like your life depends on it. Because believe it or not, it does.