Sleep is so important for the health of our brains, it’s hard to know where to start: what function of sleep is the most important?

Let’s take a look at the top four:

1. Cleansing the brain of toxins and waste
2. Storing experience as memories you can access later
3. Rest sufficiently to muster energy for attention
4. Stabilizing mood and relieving stress

One by One: Why Sleep Matters

1. Housecleaning

In the first part of the night, our brain hoses down (with lymph fluid, not water!) the open spaces in our brain. This lymph-cleaning system was discovered fairly recently and has been called the glymphatic system. Our brains clean up all sorts of worn-out molecules, cell walls, leftover insulin, and even beta-amyloid—the molecule blamed for Alzheimer’s disease. (It’s actually not the cause; it functions more as a bandage over problems, but sometimes it gets stuck and is not easily removed.)

2. Memory Storage

After the brain is cleaned, the properly resting brain can store memories. Some go into short-term storage, and others into more permanent storage. Without this storing ability, it would be hard to ever learn anything!

3. Energy and Focus

Sufficient rest enables us to better pay attention the following day and to make decisions—all of which require energy and coordination of those short- and long-term memories. Have you ever noticed your physical balance is “off” when you haven’t slept well? The same process happens with your brain—it’s a little “off” without proper rest.

4. Stress Regulation

Peaceful and restorative sleep keeps our stress hormones at their proper level and better prepares us to face the challenges of the next day.

Is Your Sleep Actually Restorative?

If you’re one of the world’s lucky people, you sleep well every night and don’t have to think much about it. But for the rest of us, it’s smart to evaluate sleep quality and do what we can to enrich it.

Step 1: Are You Well Oxygenated at Night?

The classic sleep-apnea-snorer is just part of the low-oxygen picture. In TV commercials, you might see an exhausted, overweight, short-necked person who needs help with oxygen—but look past the stereotype: athletes can also face sleep apnea. High-level athletes who breathe through their mouths instead of their noses can impair the integrity of their airways and may need oxygen support, even though they are fit and lean.

If you think you might be a little compromised, please find a way to get yourself tested for oxygenation throughout the night. Oxygen can be measured using a simple, small bracelet worn at home—no need for a sleep lab appointment! While there are some DIY fixes for mild problems, more serious cases may benefit from a CPAP machine.

Step 2: Are You Getting Enough Deep and REM Sleep?

If you breathe easily and quietly all night, your oxygenation is probably good. The next question: are you getting adequate amounts of deep sleep (for glymphatic cleaning) and REM sleep (for memory storage)?

You can measure your sleep stages at home. Some of the best trackers include the OURA ring and the WHOOP bracelet.

What Can You Do to Improve Sleep?

• Finish eating at least three hours before bedtime.

• If you drink alcohol, finish your last drink three or more hours before bed.

• Sleep in a cool, dark room.

• Be mindful of blankets! Down (heat-trapping) blankets can overheat you in the early morning hours, causing waking for no apparent reason. Opt for cotton or a lightweight wool blanket instead—save the down for camping sleeping bags.                                                                            

• Wake up at the same time every day. Sleeping in throws off your internal clock and can make it harder to fall asleep that night.

We’re Here to Help

Please reach out to us if you have any questions about testing or improving your sleep. We are all deeply interested in the topic and have many tools for both evaluating and improving your precious nighttime rest and recovery.