Light Therapy: Supporting Mood, Energy and Sleep Through the Seasons
As autumn and winter bring shorter days and less natural daylight, some people notice changes in their energy, mood or sleep routine. Reduced exposure to daylight can affect the body’s internal timing system, particularly the sleep-wake rhythm.
Light therapy, also called bright light therapy or phototherapy, uses a specially designed artificial light source to provide controlled exposure to bright light. It is commonly used to support the regulation of circadian rhythms and may be recommended in certain situations involving seasonal changes in mood or sleep patterns.
For people managing their health at home, understanding how light exposure interacts with sleep can be a useful part of a broader daily routine.
What is light therapy?
Light therapy is a technique that involves exposure to a bright, specially designed light source for a defined period of time. Depending on the device, this may involve a light therapy lamp or wearable light therapy glasses.
The aim is to provide bright light at a time of day when natural daylight may be limited. Light is detected by the eyes and provides signals to the brain that help regulate the circadian rhythm, the body’s internal 24-hour timing system.
Many light therapy devices are designed to provide a high level of illumination, with some products offering up to 10,000 lux. The appropriate intensity, duration and timing depend on the device and its intended use, so the manufacturer’s instructions should always be followed.
Light therapy is different from ordinary indoor lighting because it is specifically designed to provide a controlled level and spectrum of light.
How does light affect sleep?
Light is one of the main environmental signals that helps regulate the sleep-wake cycle. Exposure to light during the day can promote alertness and help keep the body clock aligned with the day-night cycle.
Morning light is particularly relevant because it can provide a signal associated with the start of the biological day. Light exposure later in the day can have a different effect on circadian timing, which is why the timing of light therapy matters.
A consistent routine can therefore be useful: natural daylight during the day, lower light levels as bedtime approaches and a regular sleep schedule can all support healthy sleep habits.
Light therapy and seasonal changes
Some people experience noticeable changes in mood, energy or sleep during the darker months of the year. Seasonal affective disorder (SAD) is a form of depression with a seasonal pattern, and light therapy may be used as part of its management under appropriate guidance.
Feeling tired during winter does not, by itself, mean that someone has SAD. Persistent or significant changes in mood, sleep or daily functioning deserve proper assessment rather than being attributed automatically to a lack of daylight.
Can light therapy help with sleep?
Light therapy may help regulate the timing of the sleep-wake cycle, particularly when a person's circadian rhythm is out of sync with their desired schedule.
For example, appropriately timed light exposure in the morning may help shift the body's internal clock earlier. This can be relevant for people who regularly struggle to wake at their desired time or whose sleep schedule has become delayed.
The effect depends on several factors, including the timing of exposure, duration, light intensity and an individual's circumstances. Light therapy should therefore be viewed as a structured intervention rather than simply sitting in front of a bright lamp.
Natural daylight remains useful too. Spending some time outdoors during the day, particularly in the morning, can provide the body with a strong environmental light signal.
What are light therapy glasses?
Light therapy glasses are wearable devices designed to deliver light while the user continues with everyday activities. Unlike a traditional light therapy lamp, they do not require the user to remain seated in front of a fixed light source.
Their compact design can make them convenient for routines such as having breakfast, reading or getting ready for the day, depending on the product's instructions.
The technology varies between devices. Some light therapy glasses use specific wavelengths or light spectra, so their instructions should be followed carefully rather than assuming that all products work in exactly the same way.
Light therapy glasses and lamps: what is the difference?
A light therapy lamp is a stationary device. The user generally sits at a specified distance from the lamp for the recommended amount of time.
Light therapy glasses are wearable and can allow greater freedom of movement during the exposure period. They can also be easier to transport.
Neither format is automatically more suitable for everyone. The choice depends on the device, the intended use and personal preferences around daily routines.
How can you build light into your daily routine?
A simple routine can make daytime light exposure easier to maintain.
Start with natural daylight where possible. Open curtains or blinds in the morning and spend time outdoors during the day. If natural light is limited and a healthcare professional has recommended light therapy, use the prescribed or manufacturer-recommended schedule for the device.
Light therapy should generally be used at the appropriate time of day for its intended purpose. Avoid assuming that longer or more frequent exposure is better.
In the evening, reducing exposure to bright light and creating a calmer environment can help prepare for sleep. Keeping regular bed and wake times can also support a consistent circadian rhythm.
What about people using CPAP for sleep apnea?
People receiving CPAP therapy for sleep apnea may also pay close attention to their sleep schedule and daytime alertness. Light exposure can be part of a general sleep routine, but it does not treat sleep apnea and should not be considered a replacement for prescribed CPAP therapy.
CPAP (continuous positive airway pressure) therapy uses positive airway pressure to help keep the upper airway open during sleep. If you use CPAP, maintaining a consistent sleep routine can be helpful alongside following your prescribed treatment and care plan.
For practical comfort, Linde Homecare can also provide access to CPAP masks, accessories and other sleep-related equipment. Explore CPAP masks or discover compatible CPAP accessories.
Are there situations where light therapy needs extra care?
Light therapy is not appropriate for everyone without consideration of their individual circumstances. Certain eye conditions, medications or health conditions may require specific precautions.
Anyone considering light therapy for a medical condition, particularly depression or a significant sleep disorder, should discuss it with an appropriate healthcare professional. The same applies if symptoms such as persistent fatigue, significant mood changes or ongoing sleep difficulties are affecting everyday life.
Light therapy should also be used according to the instructions supplied with the specific device. Do not look directly into a light source unless the device instructions specifically indicate that this is appropriate.
Supporting better sleep beyond light therapy
Light exposure is only one part of a healthy sleep routine. Other everyday habits can also influence sleep quality.
Keeping consistent sleep and wake times can help reinforce the body's daily rhythm. Regular daytime activity, exposure to natural daylight and a bedroom that is comfortable, quiet and suitably dark can all contribute to a more sleep-friendly environment.
For people using CPAP, comfort can also affect the experience of nighttime treatment. A suitable mask, comfortable accessories and appropriate equipment maintenance can make a difference to the practical aspects of the routine.
Explore sleep comfort solutions or discover CPAP equipment and accessories.
When should you seek professional advice?
Persistent sleep problems, significant daytime sleepiness or ongoing changes in mood and energy should not automatically be attributed to seasonal changes or insufficient daylight.
Professional advice can help identify possible causes and determine whether further assessment or treatment is appropriate. If you are already receiving treatment for sleep apnea or another condition, light therapy should be considered alongside, not instead of, your existing care plan.