Circadian Rhythm Disruption and Shift Work

Your body runs on a master clock set by light and timing. We treat circadian rhythm as a foundation layer, rebuilding light, meal, and sleep signals, even with shift work.

What you may be noticing

You feel wide awake at midnight and exhausted at noon. Night shifts leave you foggy, hungry at strange hours, and never fully rested. Weekends shift your sleep by hours, and Monday feels like jet lag. Digestion, mood, and weight seem harder to manage.

Why it is rarely one thing

Every cell keeps time. Light entering the eyes is detected by specialized retinal cells and carried along the retinohypothalamic tract to the suprachiasmatic nucleus, the master clock in the hypothalamus. Inside each cell, clock genes run a feedback loop of roughly a day. The master clock coordinates peripheral clocks in the liver, gut, muscle, and fat, which are also set by meal timing and activity. Light, food, movement, and temperature are the time cues the body listens to.

When these cues conflict, the clocks drift apart. Research links chronic misalignment, including long-term night shift work, with higher risks of insulin resistance, weight gain, cardiovascular disease, mood disorders, and digestive problems. Melatonin, cortisol rhythm, body temperature, and appetite hormones lose their timing.

In my work, circadian rhythm is a foundation layer. By supporting the natural biorhythms of the body, we support every other system. Sympathetic overdrive is a frequent upstream driver: a nervous system that cannot downshift disrupts the cortisol curve and the evening release of melatonin. Not only poor sleep, but a whole body running on mismatched clocks.

Patterns we look for

• Sleep and wake timing across workdays and days off.
• Morning, sunset, and evening light exposure.
• Meal timing, including night eating.
• Melatonin and cortisol rhythm.
• Fasting insulin, glucose, and triglycerides.
• Caffeine timing.
• Energy dips after waking or after lunch.
• Digestive rhythm and nausea with schedule shifts.
• Chronotype and vitamin D status.

How I evaluate it

The comprehensive functional neurological exam assesses autonomic balance, pupil responses, eye movements, and balance under fatigue, which reflect how well the nervous system is coping with misalignment.

Functional labs may include a cortisol rhythm, fasting glucose and insulin, HbA1c, a lipid panel, vitamin D, ferritin, and a thyroid panel. A two-week sleep and light diary, or data from a wearable, maps your current rhythm. For rotating shifts, we plan light, meal, and sleep for each transition.

How we address it

• Get outdoor light soon after waking, and walk at sunrise or sunset when you can.
• Keep a consistent wake time across the week.
• Keep days bright and evenings dim, avoid overhead LED light before bed, and use blue-blocking glasses after sunset or after night shifts.
• Sleep in a dark, cool, quiet room.
• Align meals with your active hours and finish eating a few hours before sleep.
• Time caffeine early in your active period.
• Downshift the nervous system with breath work and calming functional neurology.
• Discuss melatonin timing with your care team.

Light is the first nutrient your clock reads. With steady signals, your clocks move back into harmony.

Book your Comprehensive Functional Medicine Eval/Neurological Exam today to discover what the contributing root causes are that are underlying your health concerns.