“Timing your sleep is like timing an investment in the stock market—it doesn’t matter how much you invest, it matters when you invest.
— Kulreet Chaudhary, MD (Neurology)

Did you know that there is actually a best time to sleep? A kind of "prime time" in the night that is the most beneficial to our sleep health?

It's true! We're not making this up. In fact, you already intuitively know what it is.

Human beings, we sometimes forget, are natural beings—part of nature. And nature is smart. So smart, in fact, that it tells us each day when we should be nodding off for that "prime time" sleep. How does it tell us?

It gets dark.

About that time, in most places of the world, it's time to go to bed.

Best selling author, Shawn Stevenson talks about sleeping at the right time in his book, Sleep Smarter. Here are a few highlights:

  • Research has shown that human beings get the most beneficial hormonal secretions and recovery by sleeping during the hours of 10:00 pm to 2:00 am.
  • Melatonin, human growth hormone (HGH), and more are secreted in their strongest doses when our sleep is lined up properly with that timeframe.
  • To get the highest-quality sleep possible, we should aim for getting to bed within a few hours of it getting dark outside. (Maybe a little earlier in the winter and a little later in the summer.)

What this essentially means is that it's not enough to just try to get 8 hours of sleep. If we are going to bed at 1:00 am and getting up at 9:00 am, yes, that's 8 hours, but we are missing out on that sweet spot time that is so crucial to hormone secretion and recovery. In his book, Beyond Training, Ben Greenfield explains why.

"Between 2:00 am and 6:00 am, your core temperature falls the most drastically, allowing for more neuron and nervous system repair, neuron growth, an upregulation of circulating T cells (the killer cells of your immune system), and a decrease in inflammation. If you can get solid sleep during this phase, you'll have a stronger immune system and less inflammation. But in order for your core temperature to drop like this, you need to have been asleep for up to 6 hours already. So if you're going to sleep at, say, midnight, your body is going to get less rebuilding and repair done between 2:00 am and 6:00 am.

"Interestingly, that drop in temperature signals your body to begin producing cortisol at about 6:00 am, which restarts the entire cycle. And so you wash, rinse, and repeat the cycle, healing your body, building new neurons, and strengthening your immune system along the way."

So now you know what you've always known, even if you've forgotten. When it comes to sleep, the when is just as important (if not more so) as the how much. So give it a shot and remember that when it's getting dark outside, that's just nature's way of reminding you to hit the sack.