I’m a pretty happy-go-lucky person. But three years ago, I moved to Idaho after being a California native my whole life. It was exciting! Four real seasons! Snow! Cozy sweaters and the whole aesthetic of it all.
Then winter hit, and something felt off.
I must be getting sick, I thought. But the cold never arrived. Maybe it’s PMS. But it wasn’t that either. Then I stopped wanting to go to the gym. I only wanted to eat carbs and sleep more. I felt heavy.
Before I knew it, my then-boyfriend asked, “Have you been taking your vitamin D supplements?”
No, I said. Why would I be?
He looked shocked. “Babe, you’ve got to take vitamin D in the winter or you’re going to be majorly depressed. It’s the winter blues.”
Depression? That seemed dramatic. But I started supplementing with vitamin D and researching seasonal depression.
Turns out, you can be mentally and chemically “normal” but still suffer from Seasonal Affective Disorder, or SAD. It’s a type of depression related to changes in seasons, and it’s surprisingly common. For most people with SAD, symptoms start in the fall and continue through winter, sapping energy and triggering moodiness.
What Does SAD Look Like?
Common signs include feeling listless or sad most days, losing interest in activities you once enjoyed, having low energy, sleeping too much, craving carbohydrates, weight gain, difficulty concentrating, and feelings of hopelessness.
Sound familiar? That was me, plus I was indulging in an extra tequila shot on NFL sundays and an extra slice of pizza without reason.
Why Does This Happen?
The cause isn’t fully understood, but several factors contribute. Reduced sunlight disrupts your biological clock (circadian rhythm), leading to depression. Less sunlight also causes a drop in serotonin, the brain chemical that affects mood. Plus, seasonal changes disrupt melatonin balance, which impacts sleep and mood.
Basically, shorter days mess with your brain chemistry. So no, it’s not “all in your head.” It’s just biological.
How to Protect Yourself This Winter
- Get enough sunlight. Spend time outdoors daily, even for a short walk. Morning sunlight helps regulate your circadian rhythm.
- Use a light therapy box. These mimic sunlight and can significantly improve mood. Use for 30-60 minutes daily, ideally in the morning.
- Exercise regularly. Physical activity releases mood-boosting endorphins. Even 20 minutes makes a difference.
- Take vitamin D supplements. Many people are deficient during winter. Talk to your doctor about the right dosage.
- Maintain a healthy routine. Aim for 7-9 hours of sleep, eat balanced meals with fruits and vegetables, and manage stress through yoga or meditation.
If lifestyle changes aren’t enough, consider Cognitive Behavioral Therapy (CBT) to address negative thought patterns, or talk to your doctor about medication.
The point is this: if you’re feeling off during winter, you’re not weak or broken. SAD is a real condition with biological causes and real solutions. Understanding what’s happening is the first step to feeling like yourself again.

Thania (TA Content Manager)