DEAR DR. ROACH: My 78-year-old father is experiencing the early signs of dementia. It has been suggested that he try a $500 device that would aim a low-intensity red LED light into his nose to stimulate his brain and stabilize or perhaps even reverse the symptoms of dementia. On the surface, it seems like a modern version of snake oil designed to separate desperate people from their money, but I am open to the idea if it might be an effective treatment. An internet search suggests that there have been limited clinical trials that have shown hopeful results, but some of the trials have been sponsored by the company selling the device. Is there any tangible evidence to suggest that photobiomodulation reduces the symptoms of dementia? — R.C.

ANSWER: The theory in light therapy is to reduce cell damage and death by reducing plaques inside neurons that are the hallmark of Alzheimer’s disease. There have been some provocative trials (small and relatively short), but in my opinion there needs to be more data before I’d feel comfortable recommending purchasing a device. The trials have not shown significant toxicities, however, and low-intensity red light is probably safe.

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