• New research found that light therapy may be useful in reducing sleep issues and psychobehavioral symptoms associated with Alzheimer’s disease.
• Experts note that people doing light therapy should aim for 2–3 sessions per week, with each session ranging from 10–30 minutes.
• More research is needed for clinical certainty regarding light therapy and Alzheimer’s disease, though it could be a valuable, complementary approach to treating the condition in years to come.

Light therapy could be a useful tool to ease Alzheimer’s symptoms, a new study finds.

Previous research has found that 90% of people living with Alzheimer’s experience psychobehavioral symptoms, and 70% of people living with Alzheimer’s experience sleep disorders.

“These often disruptive symptoms are the primary reasons for placement in a care facility, and for increases in caregiver burden and distress,” Claire Sexton, DPhil, senior director of scientific programs and outreach at the Alzheimer’s Association, told Health.

“Until we can stop or prevent the disease, it is essential that we effectively treat Alzheimer’s in those living with it, and improve quality of life for the person and family,” she said.

New research, a meta-analysis of 15 randomized controlled trials published earlier this month in PLOS One, found that photobiomodulation—a type of light therapy—can improve the sleep and psychobehavioral symptoms in people with Alzheimer’s disease.

The study was small, but a variety of therapy options were analyzed. Sexton explained that the size implies that the results can’t be translated into recommendations for individuals.

Rather, the work emphasizes the need for further research, as well as shared and standardized protocols going forward.

“It is very important that the Alzheimer’s/dementia research field addresses and effectively treats the challenging symptoms and behaviors common to people living with Alzheimer’s, in addition to treating the cognitive symptoms, changing the course of the disease, and eventually preventing Alzheimer’s and all other dementias,” she said.

Here’s how light therapy may help those with Alzheimer’s disease.

Light Therapy’s Range of Benefits May Directly Ease Alzheimer’s Symptoms

There are a variety of light therapy options, but the new study focused specifically on photobiomodulation to see how it impacted people with Alzheimer’s.

Photobiomodulation is the use of light (typically using red light) for modulating cell function, Dale Bredesen, MD, a neuroscience researcher, neurodegenerative disease expert, and author of The End of Alzheimer’s, told Health.

“It has a wide range of effects, from reducing pain to increasing healing, reducing inflammation, improving sleep, and enhancing cognition,” he said.

During light therapy, the light is absorbed by cells and provides energy support, he explained. This also increases blood flow.

According to the study, light therapy can help people fall asleep faster, reduce nocturnal insomnia, increase total sleep time, and improve sleep quality. It also can improve cognitive function, enhance quality of life, and reduce caregiver burden in people with Alzheimer’s.

Some of these physical benefits could be due to the effect that light therapy has on melatonin, Bredesen explained, which is directly tied to sleep. Meanwhile, improvements in behavior could be tied to the fact that light therapy reduces inflammation and improves blood flow, he said.

“Light therapy...also influences serotonin and dopamine levels, contributing to improved mood and cognitive function,” Logan DuBose, MD, a geriatrics specialist and co-founder of Olera, a dementia care group, told Health.

He explained that the combined impact on neurotransmitters makes light therapy a valuable intervention for enhancing sleep quality and psycho-social well-being.

For light therapy to be useful, Bredesen explained that people usually need two to three sessions of therapy per week—ideally 10 to 30 minutes per session. Most often, light therapy is used in the evening, though if people are particularly struggling with waking up, they may prefer to do it in the morning, he said.

“Light therapy can improve sleep patterns, reduce night-time restlessness, and address mood-related symptoms and sundowning, fostering better overall psycho-social well-being,” said DuBose.

He explained that, additionally, light therapy’s influence on circadian rhythms has been associated with cognitive benefits.

Consequently, DuBose said that light therapy could potentially preserve cognitive function and slow cognitive decline in people with Alzheimer’s.

This, ultimately, could enhance the overall quality of life for those affected by Alzheimer’s disease.

But, More Light Therapy Research Is a Must

While the results of the study are encouraging, more research is needed for any clinical certainty on how light therapy impacts Alzheimer’s.

It is possible that this non-invasive treatment option could become an important tool for managing some symptoms associated with the disease, but it is too early to recommend it as a protocol for treatment.

“The results [of this study] suggest that the combined evidence, though modest in scale, is encouraging but preliminary, and justifies further research in larger, more representative study populations,” Sexton said.

She explained that if additional research indicates that light therapy can be used for Alzheimer’s, it would be a valuable non-pharmacological intervention that’s safe, non-invasive, and perhaps more cost-efficient than other options.

While light therapy research is still in its infancy, it may be a complementary approach to Alzheimer’s alongside other treatments in the future.

If you have any questions or concerns about light therapy or how it could impact your health circumstance, consult a trusted healthcare professional.