This weekend we set our clocks back. While many celebrated an extra hour of sleep, I cringed at the thought of darker days ahead.
Changing the clocks and shifting toward winter seems to throw many of us off track. Why does setting the clocks back just one hour cause so much havoc — igniting a feeling of “blah,” sluggish energy, and sudden weight gain?
As a pragmatic optimist, I embarked on a mission to outsmart the “blahs” this week. I reviewed the research of leading chronobiologists who study how our internal clocks and circadian rhythms interact with light.
What I learned from the literature is that light is the strongest signal for our internal clocks (yes, we have several!). These clocks coordinate countless biological processes—everything from hormone production to how efficiently we metabolize food. Our master clock, located in the hypothalamus, synchronizes the body’s systems to the daily light-dark cycle.
Morning light acts as a reset button for this clock, telling the brain it’s time to suppress melatonin (our sleep hormone) and start ramping up cortisol (our alertness hormone). When morning light exposure drops or darkness arrives earlier, the timing of these hormones shifts. The result can be disrupted sleep, lower mood, and changes in how we process food and energy. Because these systems are interconnected, even small changes or misalignments ripple outward—affecting metabolism, appetite, and emotional balance. You might notice fatigue, irritability, sugar cravings, or slower workout recovery. For those who track health data, you may even see changes in glucose or triglyceride levels.
The good news is that when we “fall back” to Standard Time, as we did this weekend, our internal clocks become more in sync with natural daylight. Ultimately, this supports better sleep, steadier mood, and even healthier metabolism. Still, the shift itself can feel rough for a few days. Even though we gain an hour, our internal clock doesn’t reset overnight.
Use the next two weeks as an adjustment period to re-synchronize. Light remains the strongest signal—here is a plan to optimize light and lock in healthy behaviors:
- Get outside within an hour of waking for 10–15 minutes of real sunlight. Consider using a light therapy lamp early in the morning.
- Keep your sleep and meal times consistent.
- Avoid bright screens after dusk.
- Move your body during daylight hours.
- And don’t underestimate the power of staying connected and active—social and physical rhythms help stabilize biological ones.
It usually takes a week or two to realign, so be patient. Keep your routines steady and give yourself some grace. Your body is adjusting to a real environmental change.
If you want support aligning your sleep, mood, and metabolism as we head into the darker months, I can help. I’ve got evidence-based strategies and tools to keep your habits strong, your mood lifted, and your metabolism working with you—not against the clock.
Next time, I will follow up with some tips and tricks on how to reduce blue light and doom scrolling! More to come…
Live Well!
Carolyn Kontos, MS, ACC, Leadership and Wellness Coach, offers Wellness & Nutrition Coaching at the JCC through her Eat Well Programs. For more information, contact Carolyn at [email protected]
