2025 October 28 Sleep well for a strong brain

You can view the Facebook video here.

Hi, this is Jim Cranston from 7EveryMinute and 7EveryMinute.com, the podcast and website about reimagining your life. Thanks for joining me today to talk about how you can sleep your way to brain health. If you like what you hear today, please leave a like, subscribe, tell your friends, and send me a message.

Last week we talked about brain health and how complex it really is. You may recall that due to some very recent research released this year in 2025, the brain might be over 2000 times more complex than previously expected. 

Tonight we're going to talk about a different aspect of brain health and body health with a quick introduction to sleep and the huge role it plays in our health. Last week we also talked about how when we sleep, there's a process in the body that circulates cerebrospinal fluid through your brain to help clear out waste products and help rejuvenate the brain.

It's called the glymphatic system. The glymphatic system works best during deep sleep because the brain relaxes and there are more spaces exposed for the glymphatic system to clear out the waste between brain cells. This brain washing has also been associated with decreased incidence of Alzheimer's and Parkinson's disease by clearing away damaging amyloid beta proteins that are often associated with various neurological diseases.

However, the brain washing by the glymphatic system works best when you're in deep sleep. Why? When you go into deep sleep, the neurons in your brain slow down their activity. When they slow down, they need less energy. If they need less energy, there's less blood flow. That reduction in blood flow is what allows the brain to shrink slightly. The cells themselves shrink to provide more spaces for the cerebrospinal fluid (CSF) to get in and clean everything out. It's also the time when the brain tidies up the day's work of learning via neuroplasticity and neural reorganization.

Other studies have shown that this process is affected by our sleep-wake cycle and circadian cycles. What are circadian cycles? They're kind of our basic time clock in our body. It's part of the reason that you can wake up automatically in the morning and feel sleepy at night. It's similar to the length of the day, 24 hours, and plays a role in regulating various bodily functions including sleep, wakefulness, body temperature, hormone production, metabolism, and lots of other things in your body.

It's related to the sun, and so there are non-visual sensors in our eyes that respond to a specific wavelength of light to help keep track of the time of day. The name of the color that they respond to is called, naturally, sky blue.

So this is all interesting, you might say, but how does this affect me? Remember this all started talking about a happy brain, and then somehow sleep got involved, and related to sleep was this thing called circadian cycle that helps regulate sleep and much more. And this is where it all comes together.

This will be a very simplified introduction and overview. There's Bios Lighting. I draw a lot from them. Full disclosure, I used to own a circadian lighting company and also worked as an affiliate and integrator with Bios Lighting and Robert Soler, one of the founders. Robert's a pioneer in circadian-friendly lighting and I quote him rather freely in a lot of the things that I do. While I still follow Robert closely because his work in healthcare is amazing, my lighting company and any direct affiliation has ended, so no conflict of interest. Love Robert's work. A big shout out to Robert and to Bios Lighting for all their work on light and light health, especially for the aging and those in care facilities.

Even though they did a lot of basic research, this is all supported by a lot more than just one company. It's really fascinating, the degrees of systems in our body to help us live nicely in the place that we are on earth. That's another whole very large discussion.

But in our modern society, we're often exposed to lights with strong blue content. When we're at work, that may not be so bad, at least at a superficial level, but much of that blue light content originates from things like our cell phones, our computer screens, inexpensive high efficiency light bulbs, high efficiency outdoor lighting, and more.

Part of what helps us to have a good night's rest is obviously getting tired. We don't normally think much about getting sleepy, but there's actually a lot that's going on besides a yawn or two. Some alertness hormones decrease while hormones associated with sleep increase. Your body temperature starts to decrease, your brain slows down as we described above. All sorts of changes start to happen, and what triggers many of these? You guessed it: your circadian cycle and the non-visual cortex in the eye.

So hopefully you're starting to see the issue that's forming here. Just before bed, say you sit down and read a book on your phone for a little while. If it's in color or you don't have the blue blocking feature turned on, you're flooding those sensors in your eyes with the exact color of blue that tells your body it's dawn, it's time to get up. You're tired, maybe even exhausted, but for some reason now you aren't sleepy. It's because that core circadian cycle got fooled and triggered into thinking the day is just beginning again.

Clearly what I just described is not a good situation. It's time for sleep, but your body's all ready to wake up. As implied above, most modern phones have an evening mode or night mode which reduces the blue content of the phone. But don't forget about the other lights in your house and your computer screen too.

We flood our lives with blue light these days, and you should consider using the features you have available or getting light bulbs for your house that don't have that blue piece of the spectrum. It's 490 nanometers if you're technically interested, but it's that little blue piece that is truly sky blue. You can either get lights that don't have that, or you can wear blue blocking glasses. People say, "Oh, those glasses," or "If I turn this phone feature on, all the colors look different." You really kind of get used to that pretty quickly.

Remember that sleep's only part of this discussion because we're also focused on brain health. If you have to make a couple of small changes so that you can go to sleep and help your brain work well, seems like a pretty small price to pay. All sorts of really important processes happen in your brain while you're asleep. We talked about neural reorganization and learning, the washing away of waste products because the brain could relax and leave more open spaces for that CSF, the cerebrospinal fluid to work. That allows the brain to heal, plus in the rest of your body, there are a lot more healing and repair processes going on.

Remember from last week: we need a well-functioning body to have a healthy brain. Your brain takes a lot of energy, so your body needs to be able to process food to make that energy and to get around without needing a lot of repair functions because you're not damaging your body as well.

So it's not that you just didn't sleep well, it's that you didn't allow your brain and your body to heal as they need to every single day. This is why when you don't get a good night's sleep, you not only have trouble waking up, but often that following day is kind of a real challenge too. It's just a little foggy. You're just not on your best game. It's because all the things that normally help you rejuvenate yourself overnight didn't happen.

You might be thinking to yourself, well what about if I go through a different time zone? Or what about shift workers who work the third shift? The same sort of effects can happen in these circumstances as well. Actually, a lot of Robert Soler's early research was done exactly to address this, specifically with NASA for the International Space Station. I told you he knew his stuff.

Think about the astronauts in the space station. They're in an environment that either has lights on all the time or is in pitch blackness if they're outside working. Your circadian cycle has nothing to key off of, and so they actually made little rooms, little areas where they could expose your body to the right frequency, the right wavelength of light, so that your body would get onto a regular cycle.

I said before it was about 24 hours. The Earth is exactly 24 hours, more or less - a little oxymoron there. But your body usually isn't quite, and there's a real good reason for that because the length of the days are always increasing or shortening. So the daylight section of it's changing every single day. Your body is used to having a little bit of variation all the time.

That's why over the seasons, the day where I am in the northeast goes from probably over 12 hours down to seven hours or six hours of sunlight or something, maybe a little less. Big change season to season, but it takes a whole year. When you fly in a plane and go somewhere else, suddenly now you've crossed three time zones or five time zones or more. Now your body really has to work to get readjusted, and that takes a few days. There are tricks you can do to help that.

That's why jet lag even exists because your body is on a schedule. It may not know exactly how long that schedule is, but it has a pretty good idea. All of a sudden now you move that schedule by five hours or six hours or 12 hours, and your body's kind of like, "I know it's time to go to bed, and the sun's just coming up. I'm really confused." And that's the jet lag.

A lot of interesting things going on in circadian cycles, how your body adjusts, how you sleep and the quality of your sleep, and your brain health. All good stuff.

So quick recap: We're all concerned about brain health naturally, especially as we age. One of the most important aspects of brain health is sleep, along with good physical health and conditioning. Two of the best ways to give your brain a better chance of staying healthy are also some of the simplest.

First, strive to get adequate and quality sleep, and that may mean limiting device usage or wearing blue blocking glasses or rearranging your schedule slightly, maybe changing the light bulbs in your house. The changes are relatively minor compared to the potential benefits, which can be huge.

Second, try to be as active as you comfortably can be. As always, please consult with your doctor or medical provider before making any health or activity-related changes. But by doing what's physically allowed and trying to focus on getting quality rest, you're helping your brain in some of the best ways possible.

So that's it for tonight. When you're home, think about your nighttime routine, especially the hour or two, maybe even three before you go to bed. Write down all the things that you do, and then also the next morning when you wake up, write down if you woke up feeling rested or not, if you thought you had a good night's sleep or not. Extra points if you discover some things that might be affecting your circadian cycle and the quality of your sleep. Then make some goals for how you can reduce or eliminate the effects of those activities. Your brain will definitely thank you.

As always, thank you so much. Remember, one of the best ways to care for yourself is to care for others. If you want, take a look at UKR7.com or WCK.org, two international sites for care - one for Ukraine, one for disasters. There was a big hurricane that hit Jamaica with 160 mile an hour winds and a predicted 40 inches of rain. Think about 40 inches of rain - that's taller than your table of solid water. That is just a mess. World Central Kitchen works in places like that, but even something as simple as a smile can change someone else's day for the better in ways that you can't even imagine.

So as always, thank you for stopping by. If you found something interesting or useful, please pass that along. Subscribe, hit that like button. If not, please drop me a comment as to what you'd like to hear. Have a great week. Remember the life that you dreamed of because that's the path to true contentment. Love and encouragement to everyone.

See you next week on 7EveryMinute and 7EveryMinute.com. Thank you.