Welcome to Insight into Health, my radio show on listener-supported KSVY 91.3, where I explore ways to make healthy living realistic, enjoyable, and sustainable. I am your host, Allison McKeany, and these are the show notes for the live radio show that aired on January 5th, 2026
Listen to the episode:
Beyond the What: Circadian Rhythm & Sleep
I love to sleep. And it seems that I have been needing even more sleep this time of year. For as long as I can remember, I have been the early bird of my family and friend group.
What is it that makes me such an early bird? Why does my husband catch his second wind just as I’m winding down for the night?
It all has to do with our individual circadian rhythms.
Your body runs on a roughly 24-hour cycle known as a circadian rhythm. Almost everything in your body follows this rhythm — sleep and wakefulness, release of all sorts of hormones, body temperature, digestion, reaction time, and more.
While your unique rhythm is related to specific “clock genes,” they are influenced a great deal by your environment.
The biggest environmental factor affecting your circadian rhythm is light. The type and amount of light that enters your eyes affects how much melatonin your body produces.
Melatonin helps to initiate sleep (it doesn’t help you stay asleep).
More light = less melatonin produced = less sleepy.
Less light = more melatonin produced = more sleepy.
This light-dependent melatonin system evolved to be responsive to sunlight:
As the sun rises and goes higher into the sky, the more awake and alert we typically feel.
As dusk and sunset descend into darkness, drowsiness starts to take over.
Our current electricity-fueled environments often confuse this system:
Being exposed to artificial light after sunset (overhead lights, screens, etc.) can suppress melatonin production, making it harder to fall asleep.
Spending more time indoors prevents melatonin from being suppressed during the day, making it hard to feel fully awake.
To combat this confusion, there are things you can do to support your melatonin, sleep, and circadian rhythm:
Within 1-2 hours of waking, expose yourself to sunlight for at least 20 minutes. This will decrease your melatonin, making you feel more alert.
Starting 1-2 hours before you’d like to be asleep, decrease the amount of light that you are exposed to. Use dimmer switches, turn off overhead lights in favor of lamps, turn on “night mode” on your screens, and consider turning them off completely before you get into bed.
Use blackout curtains or an eye mask, and remove (or cover) even the smallest of lights. Even things like a lit-up alarm clock or blinking computer monitor can disrupt sleep.
While your circadian clock is “built in,” there are external clocks that compete with your body’s natural rhythms:
Responsibility clock — daily obligations, such as the timing of work or school
Social clock — the norms of a social circle, such as late nights out or early morning meetups
When your responsibility and social clocks differ from your circadian clock, that difference will likely hurt your sleep, energy, and health.
While light plays the largest role in melatonin production, several other factors also affect your circadian rhythm:
Temperature — cooler body temperatures promote drowsiness and deeper sleep.
Activity — while being more physically active earlier in the day can help you fall asleep and stay asleep, it is best to avoid vigorous or strenuous exercise for several hours before bed.
Eating — digestion and metabolism disrupt your circadian rhythm, making it harder to fall asleep and stay asleep because of tossing and turning or heartburn.
Several other environmental and lifestyle factors affect sleep, as well; this is a great resource to explore.
Finally, while you may be tempted to rush out and buy a melatonin supplement to boost your circadian rhythm, it is best to first check with your healthcare provider and experiment with the lifestyle factors that may be preventing quality sleep.
Your doctor will likely want to rule out other causes of sleep difficulty, including medications, supplements, or diagnosable conditions like insomnia and sleep apnea.
And while melatonin supplementation may play a role in supporting your circadian rhythm, there is (of course) a ton of nuance in the type, timing, and amount to use.
I could go on. There is so much more to sleep. But for now, if good sleep has felt elusive, the answer may be in the clock your body has been keeping all along.
The take-home here is that your body has a built-in rhythm. Understanding this rhythm is the first step to supporting it.
Let’s Talk: Melissa Agocs
I was joined by my friend and neighbor, Melissa Agocs, who is also the Youth Programs Director and Dance & Movement Director at Sonoma Community Center. We talked about the many exciting programs that Melissa has introduced to the center, including adult tap and swing dance classes.
We also discussed my first Sonoma Community Center class and cooking demo, “Insight into Health: Healthspan & the Kitchen,” scheduled for THIS Saturday, January 10th, 2026:
Thanks for being here. Please remember to send your questions and topic inquiries to insightintohealth@gmail.com or leave a comment below.
~Allison