I could totally be a perpetual student.
Especially in September, when everything reminds me of my campus days. A fresh notebook, a crisp fall morning, coffee in hand, and that quiet joy of being part of something bigger.
Even now, decades later, September still feels like that, especially watching Norah head off to college.
There’s a collective energy this time of year… a new season, new beginnings, new intentions, everyone starting again, together.
It’s a clean slate. A fresh start. And my body instinctively wants to reset.
But here’s the thing: that’s not just a mood, it’s biology.
The Metabolic Rhythm of September
Our bodies are designed to respond to seasonal cues.
In the summer we get generous amounts of UVB light, which acts as a biological signal of abundance. UVB exposure drives vitamin D production, which helps regulate hormones, bone health, and immunity. Longer days and strong sunlight stimulate dopamine and serotonin. This effects our mood (for most, happier) and pushes us outward — toward more activity, more movement, more connection.
Our summer metabolism reflects this “season of outward energy.” We crave lighter foods that were grown in the summer sun, like peaches, zucchini and watermelon. We feel more active in the evenings because the days are longer and our biology is tuned into expansion.
But as September arrives, that signal shifts. The angle of the sun changes, UVB is less abundant, and we receive more red and infrared light. Instead of pushing outward, the body begins to turn inward. Our appetite changes, we want to slow down, go to bed earlier, ground, and restore. We suddenly start craving roasted squash instead of a cold salad and swap “happy hour” for a quiet walk after dinner.
This is why September feels like an invitation to pull back into structure, reset rhythms, and eat in a new way.
Circadian Biology at Work
I like to think of September as a gentle circadian nudge:
Shorter days mean longer melatonin windows. Your body is getting primed for deeper sleep (if you let dark nights be… dark).
Cooler mornings encourage metabolic flexibility. Light movement outside at sunrise can help reset hormones and appetite.
An earlier sunset means an earlier dinner meal. This isn’t about rules, but resonance — eating with the sun allows digestion and blood sugar to stay in sync with circadian timing.
This is your circadian rhythm in action. Your environment is literally scripting your biology.
Purpose as a Biological Rhythm
September can also be an invitation to reconnect with your purpose. Fall has historically been a time to move toward something — new classes, new goals, a new job, etc. There was a shared energy of purpose in the air. I believe we need that nudge of direction.
It’s actually not just me being philosophical, either. Purpose is deeply biological. Research shows that people with a strong sense of meaning in their daily lives have better heart rate variability (HRV), which is a marker of nervous system resilience. Purpose has been tied to improved sleep quality, steadier hormone response, and even lower markers of inflammation.
When you’re living in coherence with your purpose and your daily actions reflect what truly matters to you, your body registers this as safety. Your stress hormones normalize, your body recovers easily from the day, and your biometrics shift toward balance. You can actually track this for yourself with devices like an Oura ring (I do).
Purpose can look different to everyone and it doesn’t have to be epic stuff. Small daily actions that line up with your bigger “why” might look like a morning walk at sunrise, cooking dinner with your partner instead of grabbing takeout, making time for friends, even learning to play pickleball!
Purpose is a rhythm. And when we align with our purpose, all of our rhythms (metabolic, circadian, emotional, etc) fall into sync.
Your September Syllabus
If summer was the season of growth and expansion, September is the semester of structure and reset.
This means your body wants to:
Shift meals a little earlier (especially dinner)
Eat more grounding foods like squash, apples, root vegetables
Recalibrate sleep to match longer nights
Rest more intentionally instead of “pushing through”
Think of this as your own internal syllabus for fall. When you follow it, you’ll feel more in sync with nature, your body, and your biology.
The effect of seasons on our physiology is one of the reasons I created my 21-Day Rhythm Reset. It’s designed to help you practice aligning with the season’s natural cues instead of overriding them.
If you’re feeling called to reset your rhythm for fall, you don’t have to wait — we’re already inside. The moment you join, you get instant access to the daily audio trainings, handouts, and guides. You can start syncing your body with the season today.
👉 Join me inside the 21-Day Rhythm Reset. Step into fall grounded, energized, and in flow with your biology.
Mantra for September
I align with the season. I live with purpose. My rhythms are my strength.