Daylight Saving Time Ends: Your Body’s 1-Hour Jet Lag

by | Nov 3, 2025 | General

Daylight Saving Time Ends: Your Body’s 1-Hour Jet Lag

November 3, 2025 – “Fall Back” Edition
Read time: 4 minutes – Share with anyone who hit snooze twice today

1. What Actually Changed at 2:00 a.m.?

Clocks moved back 1 hour, giving you an extra 60 minutes of morning light but stealing it from the evening. Your body doesn’t read clocks—it reads light. That single hour shift can misalign your suprachiasmatic nucleus (SCN), the brain’s master clock in the hypothalamus, for 3–7 days.

Hormones & Systems Disrupted (Science-Backed)

System Immediate Effect Peak Disruption Fix Timeline
Melatonin Delayed onset by ~45–60 min Nights 1–3 Normalizes in 4–5 days with light protocol
Cortisol Morning peak arrives 1 h later than body expects 6–9 a.m. Re-anchor with sunrise viewing
Dopamine Afternoon “reward” dip; 32 % ↓ in striatal release (JAMA Psych 2023) 2–5 p.m. Micro-breaks in natural light
Thyroid (TSH) 18 % transient drop in TSH pulse amplitude (JCEM 2021) Day 2–4 Protein breakfast
Glucose Insulin sensitivity ↓ 12–19 % for 48 h (Diabetes Care 2022) Post-meal spikes Finish eating 3 h pre-bed
Appetite (Ghrelin) Evening surge ↑ 27 % (Obesity 2024) 7–10 p.m. Red light + early dinner

2. The 3-Phase “Fall Back” Protocol

MORNING (within 15–30 min of waking)

  1. Sunrise gaze – Stand outside (or balcony) for 2–10 min. Cloudy? Still works—10,000 lux trumps indoor 300 lux.
    Mech: Activates ipRGCs → SCN → melatonin offset + cortisol spike.
  2. 30 g protein + 15 g fat within 60 min of waking.
    Why: Stabilizes blood sugar; prevents compensatory hyperphagia later (Am J Clin Nutr 2023).

☀️ AFTERNOON (every 90–120 min)

  • 3–5 min natural light micro-break.
    Data: 3 min outside = 45 min mood boost (Env Psych 2024).
  • Outdoor movement priority – walk, air squats, kettlebell swings.
    Bonus: 10 min green space = 20 % ↓ cortisol (Front Psychol 2022).

EVENING (2–3 h before target bedtime)

  1. Lux < 10 – warm bulbs (2700 K) or red panels.
    Mech: <10 lux preserves 90 % of melatonin vs 100 lux which suppresses 70 % (J Pineal Res 2021).
  2. Last bite 3 h pre-bed.
    Why: Gastric emptying → no reflux + stable glucose.
  3. Cool room (60–67 °F) + consistent sleep/wake times ±30 min.

3. Bonus Hacks (All Peer-Reviewed)

Modality Protocol Key Paper Outcome
Red Light Therapy 10 -14 min evening Photobiomod Med 2023 ↑ melatonin 39 %, ↓ sleep latency 52 %
Cold Plunge 1-2 min @ 40°F Eur J Appl Physiol 2024 ↑ cortisol 46 %, mood ↑ 29 %
Cryotherapy 3 min Front Physiol 2022 ↓ afternoon ghrelin 22 %
Sauna 15–20 min  4–7×/wk Mayo Clin Proc 2023 ↑ circadian gene expression (PER2, CLOCK)
Float Therapy 60 min EPSOM tank PLoS ONE 2021 ↓ cortisol 31 %, ↑ theta waves

4. Quick Wins Cheat Sheet

  • Phone: iPhone Night Shift 6 p.m.–bed; Android “Extra Dim” + red filter.
  • Glasses: Blue-blockers only after sunset
  • Supplements (if needed):
    – 200–400 mg magnesium glycinate 1 h pre-bed.

5. TL;DR – Your 24-Hour Script

Wake → 15 min outside → 30 g protein  
Every 90 min → 3 min sunlight  
6 p.m. → dim + red  
Last meal 3 h pre-bed  
Sleep 60–67 °F  
Bonus: 10 min red light, 3 min cold plunge, 60min Float

Share this newsletter—your friends will thank you when they’re not zombie-walking through Wednesday.