Northwestern Memorial Hospital and nearby facilities are accessible today. Please monitor news for curfew information and traffic reports. Visit the Chicago Transit Authority and Metra sites for updates to travel restrictions. LEARN MORE.

Visitor restrictions are in place due to COVID-19 (coronavirus). Review the latest information about the virus and how you can help by donating funds.

Healthy Tips

4 Surprising Ways Shorter Days Affect Your Brain

And How to Adapt

Feeling sluggish? The culprit might be your circadian clock, which takes cues from how much light you’re exposed to over the course of a day, and tells you when to be asleep and awake.

Shorter winter days mean less light exposure, causing changes to your circadian rhythm.

“Our body, including all of our organs, is aligned to match the environment. It’s a beautiful symphony orchestra,” says Phyllis Zee, MD, PhD, Northwestern Medicine neurologist, and Northwestern University Feinberg School of Medicine professor and chief of Sleep Medicine in Neurology. “It’s all coordinated through the master pacemaker, which is located in the suprachiasmatic nucleus (SCN) of the brain.”

A disruption to the circadian rhythm can impact a number of functions in your body.

How Shorter Days Impact Your Brain

Metabolism. Your brain tells your body to conserve energy, so you may be hungrier.

Energy. Your body produces a hormone called melatonin in darkness — typically at bedtime. Melatonin impacts sleep patterns and energy levels.

Attention. Alertness and cognitive function decrease due to changes in your hypothalamus, the part of your brain responsible for sleep and circadian rhythm.

Mood. Neurotransmitters serotonin and dopamine decrease, which can contribute to depression.

How to Help Your Brain Adapt to Shorter Days

Eat mindfully. Eat nutrient-rich foods and avoid late-night snacks.

Exercise. Endorphins help boost mood and metabolic activity, and decrease anxiety.

Take in the light. Get outside when possible, and invest in a lamp that replicates natural daylight.

Talk to someone. A friend, family member or physician can offer support if you are feeling down.

SAD Facts

If you can’t shake the winter blues, consider consulting a physician about seasonal affective disorder (SAD), a seasonal depression that affects 5 percent of Americans. SAD typically starts in fall and goes away in spring.

To meet the criteria for SAD, you must experience seasonal depression for more than two years. Women are four times more likely than men to be diagnosed with SAD.

SAD symptoms:

  • Fatigue
  • Disruption of sleep patterns
  • Overeating and craving carbohydrates
  • Trouble focusing
  • Social withdrawal

SAD treatment options:

  • Light therapy
  • Talk therapy
  • Vitamin D
  • Prescription medications from a psychiatrist

Feeling hungry, foggy and sluggish is a normal response to shorter days. If you continue to feel this way, consider talking to your physician about SAD.

Download 4 Surprising Ways Shorter Days Affect Your Brain
Phyllis C. Zee, MD  PhD
Phyllis C. Zee, MD PhD
Nearest Location:
Rated 4.8
star star star star star
36 Ratings
Professor, Feinberg School of Medicine
  • Primary Specialty Sleep Medicine
  • Secondary Specialty Neurology
Accepts New Patients
View Profile

Where Sleep Medicine Meets Your Life