Alzheimer’s light therapy uses the power of your internal clock to help reduce some of the symptoms and effects of Alzheimer’s disease.

Alzheimer’s disease is the most common cause of dementia. It’s not a normal part of aging and occurs when protein deposits build up inside cells and between neurons, disrupting proper function.

While memory loss is the most common symptom associated with Alzheimer’s, this neurodegenerative condition can affect thinking, reasoning, decision making, mood, and behavior.

Alzheimer’s is progressive and has no cure, but innovative treatment options like Alzheimer’s light therapy may help alleviate certain symptoms.

Light therapy is the controlled adjustment of your circadian rhythm using light stimulation.

Your circadian rhythm, also known as your body’s internal 24-hour clock, controls your sleep-wake cycle by responding to how light around you changes. On the cellular level, it allows cells to recognize what time of day it is so they can perform specific functions.

Light therapy uses artificial light to help reset your internal clock when things are awry.

Dr. Carolina Estevez, a clinical psychologist from Miami, explains, “By using specific wavelengths of light, it can change the chemical makeup of your brain and boost its levels of serotonin and melatonin. The increased amount of these two chemicals can help reduce stress, regulate moods, and increase energy.”

It may seem unusual to use a circadian rhythm-focused therapy on a neurodegenerative condition, but sleep-wake dysfunction is a prominent part of life with Alzheimer’s.

Research indicates sleep disorders occur early in the course of Alzheimer’s and worsen as it progresses. Daytime napping and sleep-wake cycle shifts are common.

“Light therapy may have some benefits for individuals with Alzheimer’s disease,” says Dr. Brandon Santan, a board certified clinical mental health counselor from Chattanooga, Tennessee.

“Research has shown that exposure to bright light can help regulate the sleep-wake cycle in individuals with Alzheimer’s, which can help improve their overall sleep quality and reduce symptoms such as agitation and wandering.”

Research into Alzheimer’s light therapy is limited but promising. One of the most recent studies, published in 2021, found blue-light enriched light therapy helped improve sleep and cognitive function in people living with Alzheimer’s.

One of the largest reviews of existing research was conducted in 2013. It found bright light therapy was effective in Alzheimer’s for reducing daytime sleepiness and increasing overnight sleep.

Light therapy and dementia

More research exists on light therapy for dementia rather than Alzheimer’s, primarily because dementia covers a broader spectrum of conditions.

A 2021 study, for example, found that 30-minute sessions of bright light therapy had immediate, positive effects on mood, mental stimulation, heart rate, and blood oxygen saturation in people living with dementia.

“Improving sleep quality can have downstream effects of improving symptoms such as agitation and wandering,” Santan says. “There is research also that suggests that light therapy may improve cognitive function and decrease depression in individuals with dementia.”

Alzheimer’s is a common cause of dementia. As such, research that supports dementia light therapy may also have implications for Alzheimer’s disease.

Can light therapy prevent dementia?

Animal research suggests certain wavelengths of light may be able to slow and protect against processes of neurodegeneration.

A 2022 study conducted in mice found low intensity light therapy slowed neurodegeneration by reducing oxidative stress and, therefore, reducing protein accumulation in the brain.

Human clinical trials are underway to see whether this could one day be a true means of preventing or successfully treating Alzheimer’s disease and other dementias.

Your sleep-wake cycle matters. It influences everything from digestion to hormone function. Sleep is when your body consolidates memory, promotes healing, and regulates metabolically.

If you’re not sleeping well or enough, these important processes can go haywire.

By regulating your sleep-wake cycle, Alzheimer’s light therapy may:

  • reduce daytime sleepiness
  • improve duration of overnight sleep
  • boost mood
  • reduce agitation
  • improve cognitive function

Bright light therapy is one of the most well-researched forms of Alzheimer’s light therapy.

“Generally, the most effective type of light therapy involves using a special device that emits a specific type of bright white light,” Estevez says. “This device can be used at home and should be used daily, typically in the morning or evening.”

Santan explains the recommended intensity of the light used in bright light therapy for Alzheimer’s is at least 1,000 lux, and exposure times can vary from 30 minutes to 2 hours a day. The time of day you use light therapy can be important, however, and it’s a therapy that should be done with the guidance of a medical professional.

As for which light therapy is “best” — the verdict is still out. There appear to be unique benefits to specific wavelengths.

“The best type of light therapy for Alzheimer’s disease is still a topic of ongoing research, and there is no one-size-fits-all approach that works for everyone,” says Santan.

Alzheimer’s light therapy uses artificial light to regulate your circadian rhythm. This may help you feel less sleepy during the day, improve your overnight sleep, and boost your cognitive function.

More research is needed into the benefits of Alzheimer’s light therapy, but one day it could be more than just a sleep-wake therapy; it may serve as a treatment for neurodegeneration.