Do Tanning Beds Help With Seasonal Depression?

If exposure to sunlight can help with seasonal depression, why can’t tanning beds be used to treat it? Before we look at the reasons why tanning beds should not be used for this, let’s dive into what seasonal affective disorder is and the right way to treat it.

What is seasonal depression?

Seasonal affective disorder (SAD) is a type of depression associated with seasonality. 

It affects 0.5%–3% of the general population and is more common in people diagnosed with depression (10%–20%) and bipolar disorder (about 25%)¹. 

Typically, symptoms of depression will persist during winter, and sometimes in fall, when the daylight hours start to shorten and the amount of sunlight exposure decreases significantly. Although it is much more common for SAD to present in the winter months, for some people it occurs in the summer.

More than just the ‘winter blues,’ SAD has a significant impact on your life. Like all depressive disorders, it impacts your mood and ability or desire to function, leading to physical, psychological, and social withdrawal from your environment. Symptoms vary in frequency and severity from person to person. 

Rates are significantly higher amongst females during adolescence and middle age. Other risk factors include:

• Living in a country far north or south of the equator

• Living in higher latitudes

• The presence of other mental disorders such as bipolar disorder

• Family history

• Low levels of vitamin D

Could seasonal affective disorder be affecting you?

If you are experiencing some of the following symptoms, consider talking to your doctor about whether you may be experiencing SAD.

Common symptoms include:

• Feeling low

• Unable to feel pleasure

• Constantly feeling tired

• Difficulty concentrating

• Lack of willpower

• Increased periods of sleeping (in winter or fall SAD)

• Insomnia (in summer and spring SAD)

• Eating more (in winter or fall SAD)

• Increased cravings for high-calorie foods

• Weight gain (in winter or fall SAD)

• Weight loss (in summer and spring SAD)

To obtain a SAD diagnosis, symptoms must persist for two or more years. They must occur and remit during the same time of year, and the depressive episodes must be isolated to the season.

Over a lifetime, people with SAD have more particular seasons with depression than without. Please seek your health professional if you are concerned.

What causes seasonal affective disorder?

The cause of SAD is not fully confirmed. 

Research has shown that multiple chemicals in our brain (‘neurotransmitters’) during winter are altered due to decreased sunlight hours. It has also been suggested that an imbalance of our internal rhythm with the outside environment could lead to this disorder. 

Researchers do know that lack of sunlight is the key driver of this disorder. Light travels through the optic nerve (in the eye) and sends strong signals to the arousal system in our brain to release (or inhibit) several chemicals.

However, in the case of summer SAD, too much sunlight can have a negative impact on people who have difficulty adjusting to the increased daylight hours, possibly due to some genetic predisposition.

Studies have found changes in melatonin, serotonin, and vitamin D in people with SAD.

Melatonin

Melatonin is a hormone produced by the pineal gland in response to darkness. It signals to your brain that it is time to sleep. It is an essential factor for our body’s circadian rhythm and allows us to adjust to the different seasons.

When it is daytime, sunlight decreases melatonin production. The decreased daytime sunlight in the winter months leads to increased production of melatonin, which can elicit feelings of fatigue and lethargy. This can also impact the healthy circadian rhythm, causing individuals with SAD to have disrupted sleep-wake cycles.

Serotonin

Serotonin is an essential chemical in our brain, implicated in mood, appetite, and sleep regulation. It is produced in the intestine and brain stem, and excessive amounts produce feelings of euphoria. Low levels have been associated with depression². 

SAD has been associated with an increased amount of a serotonin transporter³ called SERT during the winter months. SERT acts by ensuring the reuptake of serotonin and terminating its action in the brain. Therefore, less sunlight reduces the amount of serotonin available to the brain, so it cannot function optimally. 

Vitamin D

Vitamin D is essential for the production of serotonin and our body receives most of its supply from the sun. Reduced levels of vitamin D have been found in people with SAD⁴. This limits the production of serotonin, an important mechanism for mood regulation.

One study⁵ reported a significant reduction in SAD symptoms for people who received high doses of vitamin D supplements compared to those who didn’t.

How is seasonal affective disorder treated?

Treatment of SAD is highly effective. Light therapy is the first-line treatment with about 65% of people with SAD reporting improved symptoms⁶.

If this treatment does not work or is unavailable to you, alternative methods include:

• Antidepressant medication

• Vitamin D supplements

• Cognitive behavior therapy

What is light therapy?

Light therapy aims to increase the amount of light that the brain receives. This treatment involves a device called a lightbox, that emits 2,000–10,000 lux of visible light on an individual for approximately an hour per day in the winter when symptoms are present. 

Typically, this treatment is used for six weeks. It can take just a few days to a few weeks for people to feel an improvement. This treatment is generally accepted as the best one for SAD. Using it in the morning seems to be the most beneficial time.

Sometimes, this treatment is not advised, for reasons including some eye diseases and the use of specific medications that increase sensitivity to light, such as some antibiotics and antipsychotic drugs. It is important to discuss this treatment with your doctor before purchasing a lightbox.

What’s more, if you have summer/spring SAD, light therapy is not right for you. Your body needs to be exposed to less light during the day, so spending more time in dark rooms is recommended.

Why are tanning beds harmful?

Tanning beds are used for cosmetic purposes. They make your skin look more glossy and brown. The UV light used by these machines increases the amount of melanin in your skin, a chemical produced to protect the skin from damage and which gives the skin color.

This is not to be confused with melatonin, the sleep messenger of the brain.

Tanning beds are not a form of light therapy

Tanning beds differ significantly from lightboxes in how the body responds to them. Light therapy uses visible light which is safer and can access the brain. Tanning beds use ultraviolet light to act on the skin and have no effect on your brain. 

Damaging UV light

No research supports using tanning beds to treat SAD. The ultraviolet light from tanning beds can seriously damage your skin, leading to an increased risk of cancer of the skin and eyes.

Risk of tanning addiction

Tanning has not been found effective in treating SAD. It has also been associated⁷ with problematic tanning behaviors and ultimately tanning addiction.

The lowdown

Seasonal depression and SAD are relatively common. It can lead to depressive thoughts, lack of motivation, and fatigue, which can negatively impact your lifestyle. 

Exposure to sunlight and/or having light therapy could be effective in improving many of the symptoms. Other activities that can help are:

• Regular exercise

• A good diet of fresh food

• Avoiding alcohol and smoking

• Maintaining a healthy sleep pattern

• Taking part in social activities

Tanning beds are not the answer as they can potentially do more harm than good.