Light Therapy For Depression: Does It Work?

Reviewed by Tanya Harrell, PhD, LPC, NCC

Published 06/24/2022

Light therapy is a relatively new form of treatment that has shown results in helping people who have depression symptoms, particularly those who struggle with seasonal affective disorder. In this article, you will learn more about light therapy, how it works, and its efficacy so you can decide if it may be a good treatment method for you.


Light therapy, also sometimes known as phototherapy, is a type of treatment involving a lamp or light therapy box designed to emulate natural light.

You place the light device somewhere near where you are working or doing other activities, and over time, it should provide symptomatic relief because the light is supposed to affect your brain chemistry positively.

For example, natural light is believed to influence serotonin production, which is supposed to improve your mood, and it can also influence sleep as well. [1] [2]

Therefore, light therapy can be especially useful for those who live in locations that receive less sunlight or during the fall and winter months. This lack of sunlight has been linked to depression symptoms, and in the next section, you will learn more about this connection between light and depression.

Seasonal Affective Disorder

Seasonal affective disorder (SAD), commonly referred to as seasonal depression, is a form of depression that affects around 5 percent of the U.S. population and can last up to 40 percent of the year. [2

Most people experience seasonal depression during the fall and winter months; however, some struggle during the summer.

Although the condition is correlated with seasons, overall, the seasonal affective disorder is believed to primarily affect people who live the equator's furthest.

For example, places such as Alaska, the Nordic Countries, Argentina, and even Antarctica are known to experience depression symptoms. Due to their position on the globe, they are prone to receiving less sunlight than other places globally, which causes them to have a higher incidence of SAD.

While SAD isn’t fully understood, the lack of sunlight is believed to interfere with circadian rhythms and contribute to a chemical imbalance in the brain, much like those who deal with major depressive disorder can experience.

In fact, there isn’t a significant difference between seasonal depression and major depression. In the Diagnostic and Statistical Manual 5th edition (DSM-5) by the American Psychiatric Association, the seasonal affective disorder is Major Depression with Seasonal Pattern.

Because of this, aside from the main component of there being a lack of sunlight, SAD shares the same signs and symptoms of major depression such as [3]

  • A low mood
  • Fatigue and restlessness
  • Appetite and weight changes
  • A loss of joy or pleasure in activities
  • Feelings of guilt, worthlessness, hopelessness, etc.
  • Suicidal ideation

However, unlike major depression, which can be more persistent, the seasonal affective disorder depressive symptoms can often improve or subside completely as the problematic seasons or long periods of little to no sunlight pass.

Nonetheless, these symptoms can be challenging to cope with while they are here, and that’s where light for depression can be beneficial.

The Pros & Cons Of Light Therapy

There are many reasons why people may opt to use light therapy treatment for their depression but there other factors that you should be aware of when considering this option. Here are some of them:

Why People Try Light Therapy

  • They are seeking a safe treatment method with fewer side effects
  • They are looking to supplement their antidepressant medication regimen
  • They need to avoid medication (such as during pregnancy) and want to find an alternative
  • It’s convenient to use and non-invasive

In addition to the points above, in many cases, a depression lamp can allow patients to reduce their medication dosage depending on the progress that they are showing.

Things To Be Careful Of When Choosing Light Therapy

  • It can strain or dry out your eyes, especially if it’s placed directly in front of you
  • For some people, it causes nausea and headaches
  • Although lightboxes for depression typically filter out as much UV radiation as possible, prolonged exposure may irritate the skin or cause sunburn
  • In rare cases, it can cause irritability or aggravate manic symptoms in individuals who may also have bipolar disorder

Lights for depression are considered quite safe in general and have minimal risks, but by being aware of them and being cautious, you can get the most out of your sunlight lamp for depression.

How To Use Light Therapy For Depression

When looking for an appropriate lightbox for depression, one that produces 10,000 lux is highly recommended. Lux is a unit that measures the brightness, and 10,000 lux most closely replicates natural daylight. [4]

For light therapy to work, it’s not necessary to use it throughout the entire day. Instead, starting out with 10 to 15 minutes sessions and gradually working up to 45-minute sessions is typically sufficient. In total, a couple of hours each day should be enough to see improvements, and most people see the most benefit from it when using it in the morning. [4]

If you have a lightbox or can only get access to a lightbox that produces fewer lux than 10,000, you will simply need to increase your exposure to the lightbox to see the same effect. For example, if you have a 2,500 lux lightbox, you will need to spend anywhere from 40 minutes to an hour to get the same benefit.

There are also some additional factors you should consider when setting up a lightbox, such as [4]

  • Size- you don’t want one that’s too small since any movement can potentially remove the light from your eyes
  • Positioning - To reduce glare, try to have the lightbox facing downwards towards your face. However, some people have seen results by having it on their desks while they work.
  • Colorlessness- the light should be emitting white light as opposed to a colored one.
  • UV Filtering- try to find a box that filters as much UV light as possible. Like natural sunlight, UV rays from lamps can also irritate the skin and damage the eyes if they aren’t screened out.

Many people often see improvements within just a few days of using light therapy, but if you don’t see results immediately, don’t worry - it can take some people a few weeks to see changes, similar to how long it takes for antidepressant medications to become noticeable.

Keep in mind, if you haven’t seen any improvement and it’s been six weeks, you should consider other options or additional ones to supplement light therapy.

However, sunlamps for depression should not be the only treatment that you use if you’re struggling with any type of depression, including seasonal affective disorder. It should be used alongside psychotherapy for depression and medication, if possible.

Always consult with your doctor or psychiatrist when making changes or additions to your treatment plan.

What Else Can Light Therapy Be Used For?

In addition to depression, lighting can be helpful for a handful of different issues that people face, such as [1]:

  • Sleep disorders
  • Jet lag
  • Adjusting to a different work schedule

Light therapy can be effective for these conditions or situations because it can help adjust a person’s circadian rhythm and get them back on track and be more productive.

Do You Have Depression?

Depression, in general, has a complex set of symptoms, and a proper diagnosis involves visiting a doctor or mental health professional.

It’s more than feeling sad or blue, and it can be very persistent and significantly reduce a person's quality of life if it’s left untreated, so finding help as soon as possible is the right course of action.

If you’ve become familiar with the symptoms of depression and you’re not sure if you should still seek out assistance, consider trying this free depression test.

It takes a very short time to complete, and it can help you consider your next steps and help you start getting treated if the results indicate that you could be depressed.


Light therapy has been incredibly promising for those who struggle with depression, especially those with seasonal affective disorder. By adding a lamp for depression in your treatment regimen along with therapy and medication, you can obtain the best results possible and change your life. To find out if you may be suffering from depression, take our quick online test.


  1. Mayo Clinic Staff. (2017, February 08). Light therapy. Retrieved from
  2. American Psychiatric Association. (2020, October). Seasonal Affective Disorder (SAD). Retrieved from
  3. Casarella, J. (2019, September 17). Signs of Clinical Depression: Symptoms to Watch For. Retrieved from
  4. The University of Michigan. (, 2018). Seasonal Affective Disorder & Light Therapy Toolkit [Brochure]. University of Michigan Depression Center. Retrieved from