Search IconSearch

How Light Therapy Can Help With Seasonal Affective Disorder (SAD)

We shine a light on how light therapy can improve your mood

A child sits at the kitchen table eating while a large sun lamp shines natural light next to them.

The winter months may mean snowball fights, hot cocoa and holiday decorations, but they also means less sunlight. And less sunlight can lead to seasonal affective disorder (SAD), which is now known as a major depressive disorder with a seasonal pattern.


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

SAD is a form of depression that typically happens in the fall or winter. The lack of sunshine affects our circadian rhythms, the name given to the “internal body clock” that regulates the 24-hour cycle of biological processes in our bodies.

Reduced sunlight can also cause your serotonin levels to drop and melatonin levels to become unbalanced, which can play a role in your sleep patterns and mood.

For many, using light therapy can help treat SAD and other conditions like depression and sleep disorders.

Psychologist Adam Borland, PsyD, talks about how light therapy works and how to use it at home.

What is light therapy?

Also known as phototherapy or bright light therapy, light therapy can be used to treat SAD and other conditions by using artificial light. To use light therapy, you need to sit or work near a light therapy box for about 30 minutes.

“Especially in the winter, our bodies react to the gray, cold weather and lack of natural sunlight,” says Dr. Borland. “What light therapy does is compensate for the lack of exposure that we get from natural sunlight.”

Types of light therapy

While most light boxes or other light therapy devices use full-spectrum fluorescent light, there are also different types of light therapy that might offer benefits beyond treating SAD.

  1. Red. While more research is needed to see if using red light therapy is effective in treating wounds, ulcers and pain, there is some promise that it is helpful with fading scars and improving hair growth.
  2. Blue. In addition to helping those with SAD and depression, blue light may help with sun damage and acne.
  3. Green. Research shows that green light can be beneficial in helping those with migraines.

Light therapy benefits

Helps with SAD

About 5% of adults in the U.S. experience SAD, which tends to start in young adulthood. About 75% of people who get seasonal affective disorder are women.

If you have SAD, you may experience some of the following symptoms:

  • Sadness.
  • Anxiety.
  • Weight gain.
  • Lack of energy.
  • Trouble concentrating.
  • Irritability.


To get the most-effective and longest-lasting boost in your alertness, mood, energy and concentration, it’s important to use light therapy regularly. Research shows that light therapy is considered the best treatment for SAD.

Helps with depression

By helping your circadian rhythm and balancing serotonin levels, research shows that light therapy may improve depression.

A study shows that whether light therapy was used alone or with fluoxetine, an antidepressant medication, it was effective in improving symptoms of depression.

Helps with sleep disorders

If you have insomnia or circadian rhythm sleep disorders, research shows that using light therapy can help by positively affecting melatonin and serotonin levels in your brain.

It can also help you set up and keep an ideal sleep schedule.

Helps the effectiveness of antidepressant medication

If you’re taking an antidepressant, think of using light therapy in partnership with your medications.

“What it does is help balance and activate the serotonin in our brains,” says Dr. Borland. “So if someone is taking medication and engaging in talk therapy, all those things can certainly help with mood.”

How to use light therapy

While there are light therapy options like dawn stimulators and natural spectrum light bulbs, using a light box (a flatscreen device that uses full-spectrum fluorescent light) is the most common in treating SAD.

If you’re interested in using a light box, there are plenty of affordable options available. But Dr. Borland says to do your homework and look for one that gives an output of 2,500 to 10,000 lux (a way to measure light brightness).


Here’s the best way to use your light box:

  • Use a timer. Dr. Borland says that while the amount of time you need to use your light box differs from person to person, most people tend to use it for 30 minutes a day. “The nice thing is that most light boxes come with a timer on them,” he says.
  • Use it in the morning. Try using it as early in the day as possible, says Dr. Borland. Using it at night can have negative effects.
  • Don’t look directly into the light. Place your light box on your desk or table, off to the side. “Use it just as a passive light source and don’t look into it directly,” Dr. Borland says.

Dr. Borland cautions that you should talk to your healthcare provider before starting light therapy. It might not be the best option for individuals with vision-related conditions, those who are on certain medications like anti-inflammatories or antibiotics, people who are sensitive to light and those with bipolar disorder.

You may also experience headaches, blurry vision, fatigue and eye strain while using light therapy. If symptoms worsen, call your doctor.

But with its affordable price point and small, convenient size, using a light box can be beneficial.

“Go in with an open mind,” says Dr. Borland. “This is something that can be used in addition to medication, talk therapy, exercise and socializing — all these things that are important in life.”


Learn more about our editorial process.

Related Articles

Person in foreground hunched over in sadness as family decorates holiday tree in background
December 12, 2023/Mental Health
How To Handle Holiday Depression When It Hits Home

The holidays can be hard on your mental health, but there are ways to cope

person sitting up in bed looking out the window
July 11, 2023/Mental Health
Yes, You Can Get SAD in the Summer

If you experience warm weather seasonal depression, you’re not alone

Friends laughing and spending time together outside in winter.
December 15, 2022/Mental Health
How the Norwegian Concept of Koselig Can Get You Through the Winter

Cozying up with friends and family can make cold, dark days more meaningful

Family working out inside the house while it's snowing outside.
December 8, 2022/Mental Health
Winter Blues Got You Down? Here’s How To Cope

Step back from social media, set boundaries and spot the symptoms of SAD

Woman outside walking in windy winter weather
Can Weather Changes Make You Sick?

An expert explains how seasonal weather changes affect our health

A person wearing a white long-sleeved shirt sitting with her eyes closed
October 6, 2021/Mental Health
3 Strategies to Fight Seasonal Affective Disorder

Helpful tips to ward off the winter blues

Blue light for your health
May 5, 2021/Skin Care & Beauty
Blue Light Therapy for the Skin: What Can It Do?

Go blue to treat acne, sun damage and skin cancer

man using SAD lamp in winter
September 17, 2020/Brain & Nervous System
Will a SAD Sun Lamp Actually Make You Happy?

Light therapy can boost sleep and help fight depression

Trending Topics

Female and friend jogging outside
How To Increase Your Metabolism for Weight Loss

Focus on your body’s metabolic set point by eating healthy foods, making exercise a part of your routine and reducing stress

stovetop with stainless steel cookware and glassware
5 Ways Forever Chemicals (PFAS) May Affect Your Health

PFAS chemicals may make life easier — but they aren’t always so easy on the human body

jar of rice water and brush, with rice scattered around table
Could Rice Water Be the Secret To Healthier Hair?

While there’s little risk in trying this hair care treatment, there isn’t much science to back up the claims