Red light therapy isn’t just a celebrity spa secret anymore. The light panels you used to see in gyms and wellness centers are now showing up in bathrooms and bedrooms across the country. The home light therapy device market is set to grow to more than $600 million by 2025 (Nordvik Outdoors), showing just how much demand has shifted toward do-it-yourself care. But does it really work, is it safe, and which devices give you the most value?.