Light therapy has been shown to improve sleep quality and lift your mood, including by potentially fighting depression. One type of light therapy is the use of “sun lamps.” A sun lamp is typically a small device you can use at home daily for about 30 minutes.
Why is a sun lamp good for you?
Use of sun lamps is most popular during the winter months, when there’s fewer hours of daytime light. For some people, the darkness that accompanies winter can contribute to seasonal affective disorder (SAD), a type of depression triggered when people do not get enough natural light exposure.
SAD is thought to affect about 6% of adults in the U.S., while another 14% experience mild SAD-like symptoms. Surprisingly, symptoms can last for about 40% of the year in some people, spanning the fall and winter.
Even if you don’t have SAD, you can still probably benefit from a sun lamp if you tend to experience the “winter blues” and drops in energy, sleep quality and productivity when you’re not outdoors in the sun enough.
What Is a Sun Lamp?
A sun lamp is an intense artificial light that affects your circadian rhythm, also known as your “internal clock.” Sun lamps are also sometimes called “light therapy” or “SAD lamps.”
Most indoor light is not bright enough to cause any measurable changes in human circadian rhythms, but sun lamps are different because they emit a specific type and intensity of light that has effects on the human brain and hormone production.
Sun lamps have been used since about the 1980s to treat SAD, and today they are still the first-line treatment option for people with this condition. (Medication, therapy and exercise are also sometimes used.)
These lamps have been been shown in many clinical studies conducted over the past several decades to reduce SAD symptoms like:
- loss of interest
- poor concentration
- and others
Uses and Benefits
Sun lamps can help treat some of the following symptoms:
- SAD symptoms (hopelessness, social withdrawal, etc.)
- Insomnia and other sleep issues
- Vitamin D deficiency
- Brain fog
- Low motivation
- Weight and appetite changes
- Mood swings
How do sun lamps work for sleep and your mood?
Sun lamps work by mimicking the natural effects of sunlight. Bright light helps regulate our circadian rhythms by making us alert in the morning after waking up and then sleepy at night when it’s dark. This is due to the effects of hormones, including melatonin, serotonin and cortisol, of which circadian rhythm helps control production.
It’s thought that sun lamps can help counteract the effects of increased darkness in the winter.
Researchers believe that shorter days of light in the winter can cause people’s circadian rhythms to become out of sync and to “drift later,” messing with their sleep-wake cycles. This drift can make it harder to fall asleep and then cause morning/daytime drowsiness.
Being exposed to bright light early in the day can help push the circadian rhythm cycle back earlier, which can help with sleep and daytime functioning.
Sun lamps can also help people who are struggling to stay awake at night and often fall asleep too early. (This is common among the elderly.) They may find that light exposure in the afternoon can help mitigate this problem.
How well do sun lamps work for SAD?
It’s estimated by some experts that between 60% and 80% of SAD sufferers benefit from light therapy. Improvements in SAD symptoms can often start to be felt within just two to five days of using a sun lamp.
Can you get vitamin D from a sun lamp?
Some sun lamps emit UVB light that helps the body produce vitamin D — although not all sun lamps feature this type of light. This is one way to increase vitamin D levels among people with vitamin D deficiency. (Sunlight exposure outside, supplements and eating vitamin D foods can also help.)
Vitamin D is an important vitamin that also acts like a hormone in some ways, since it influences the nervous system, as well as the skeletal, cardiovascular and immune systems. People who spend most of their time indoors and who do not get enough exposure to sunlight are likely to be lacking in vitamin D, so light therapy may be a good option.
One downside is that UVB light can potentially harm the skin if you’re exposed to it too much.
The fact that some sun lamps increase vitamin D levels makes this type of light therapy different than red light therapy. Red light therapy, which features wavelengths between 630–700nm, does not provide vitamin D but does have other benefits related to tissue healing and reducing inflammation and pain.
Do sun lamps help skin?
Sun lamps won’t tan your skin like sunlight does. In fact, many lamps have filters that remove UVA light, the type of light that damages the skin and results in sunburns and tans.
Light therapy can support skin health in other ways, however, by increasing vitamin D levels and supporting your immune system. This might result in less inflammation that can cause various skin issues.
Risks and Side Effects
Light therapy using sun lamps is generally safe if you use a lamp made from a reputable manufacturer. It’s important to note, however, that SAD lamps and light boxes are not usually tested or regulated by the Food and Drug Administration, so make sure to do your research and buy a lamp that has many strong reviews and testimonials.
Can you use a SAD light too much? Yes, which is why you should always follow recommendations depending on the specific light.
It’s possible to experience mild symptoms from sun lamp use, such as eyestrain and headaches, or potentially more serious mood, skin and sleep issues (since these lights affect hormone levels). Side effects tend to be more noticeable in people with existing eye and skin issues (if UVB light is emitted) and those who have migraines or mental health disorders.
If you do have diagnosed SAD, speak to your doctor about using specific types of sun lamps as you would a medical device. It’s recommended that you treat SAD with your physician’s help and guidance, which may mean also using therapy, medications and other treatment approaches.
Do not begin light therapy if you have any of the following health conditions without working with a doctor:
- Bipolar disorder
- Macular degeneration
- Connective tissue damage
- Existing skin cancer
How to Use
According to experts, the standard light therapy regimen is 10,000 lux of light exposure in 30-minute sessions, shortly after waking up.
Thirty minutes is considered the minimum length of time that experts recommend to experience physiological benefits from sun lamps. The time needed depends on the type of light and someone’s goals. That can range from 30 to 90 minutes (of about 10,000 lux) of light therapy per day.
Mornings are generally considered the best time for light therapy, since this helps regulate the circadian rhythm. (It’s also why experts recommend people go outdoors in the morning and expose their eyes to natural light if possible.) In some cases, light treatments can be divided during the day.
In terms of where to use your sun lamp, this depends on the adjustability of the lamp that you purchase. With most devices you’ll need to stand or sit about two to three feet away.
An adjustable lamp is best if you plan to use it while looking down, such as while doing something like reading or writing. Other lamps need to be propped up on a desk and can’t be adjusted, so these are a bit less convenient.
Where to Buy/What to Look For
No prescription is necessary to buy a sun lamp, so look for one in retail stores or online. Lamps range from about $40 to $250+ depending on the size, strength and features.
There are a few things to consider when shopping for a sun lamp:
- Color temperature
- Type of light (remember, for vitamin D you need a light that emits UVB light)
- Whether it’s adjustable (which will affect how close to the lamp you need to sit for the treatment, plus where you can use it)
When writers at the New York Times tested 50 different sun lamps and spoke to experts about their top picks, they found that the most highly recommended sun lamps are those that offer “UV-free” LED light with about 7,000 to 10,000 lux of light intensity. Ideally the lamp should also be large, adjustable and have a UV light filter.
Most sun lamps deliver between 2,500 and 10,000 lux. The more lux a light delivers, the less time you need to spend positioned in front of it to reap benefits.
When deciding if a light is intense enough for you, consider how it feels: You’re looking for light that feels comfortable and like sitting outside on a sunny day, but you shouldn’t feel hot or overstimulated.
In terms of size, the best light therapy units are usually about a foot by 1.5 feet in surface area or larger. Bigger lights emit more light and can be easier to use — plus this cuts down on the time needed to sit on from of them.
Most experts strongly recommend light boxes with the largest surface you can afford.
Most lamps use white fluorescent lights behind a plastic diffusing screen, which filters out ultraviolet rays. This is highly recommended to protect the eyes from damage.
Lights vary in terms of their “color temperature,” which is measured by units of Kelvin. Color temperatures can range from 3,000 to 4,000 and 5,000 Kelvin, which will impact the color of the light and how “warm” it appears.
- Sun lamps are intense artificial lights that are particularly effective for people suffering from seasonal affective disorder (SAD).
- They can also benefit anyone who doesn’t get enough natural light exposure, especially during the winter.
- They help regulate your circadian rhythm and can improve your sleep, energy and mood.
- Experts recommend a lamp with about 10,000 lux brightness, a large screen and a UV-free, LED light source. Use your lamp for about 30+ minutes daily, ideally in the morning, for the best results.