Blue Light and Sleep
How Your Devices Are Sabotaging Your Rest
We’re surrounded by screens from morning to night—phones, tablets, computers, and TVs. But the blue light emitting from these devices could be the reason you’re struggling to fall asleep. As our screen time has increased, so have sleep difficulties. Here’s what you need to know about protecting your sleep in our digital age.
If you’re experiencing persistent sleep issues, don’t wait. Call Dr. Simmons at the Encino Center for help with sleep & TMJ disorders at (818) 300-0070. Schedule a consultation and start sleeping better tonight.
What Is Blue Light?
Blue light is a high-energy wavelength of light (380-500 nanometers) that naturally comes from sunlight during the day. However, artificial sources—smartphones, computers, tablets, TVs, and LED lighting—emit significant amounts of blue light that can disrupt sleep when encountered in the evening.
While natural blue light during the day helps regulate our internal body clock, artificial blue light at night tricks our bodies into thinking it’s still daytime when we should be preparing for sleep.
The Science Behind Blue Light and Sleep
Your circadian rhythm is your body’s internal 24-hour clock that regulates when you feel alert or sleepy. This system is controlled by light and darkness signals that trigger melatonin production—your natural sleep hormone.
Dr. Simmons at the Encino Center for Sleep & TMJ Disorders explains that melatonin levels typically start rising around 9 PM, making you feel drowsy. However, blue light exposure in the evening suppresses melatonin production by up to 23%, making it harder to fall asleep and disrupting your entire sleep-wake cycle.
Research shows that just two hours of evening screen time can significantly delay sleep onset and reduce sleep quality. Unlike caffeine’s temporary effects, blue light’s impact on circadian rhythms can persist for days, creating a cycle of poor sleep and increased device dependence.
Beyond Sleep: Other Health Effects
Blue light affects more than just sleep. Digital eye strain from prolonged screen use causes dry eyes, blurred vision, headaches, and neck tension. Preliminary research also suggests potential long-term retinal damage from excessive exposure.
Poor sleep from blue light disruption creates a domino effect: increased stress hormones, decreased cognitive function, impaired decision-making, irritability, and difficulty concentrating. According to Dr. Simmons, patients often report these symptoms when their sleep is chronically disrupted by evening screen use.
Common Blue Light Sources
- Smartphones and tablets: Most problematic due to proximity to your face and bedtime use
- Computers and TVs: Large screens emit significant amounts, especially during late-night viewing
- LED and fluorescent lighting: More blue light than traditional incandescent bulbs
- E-readers and backlit devices: Direct blue light exposure during bedtime reading
What Are Some Practical Solutions?
Limit Evening Screen Time
Stop using screens 1-2 hours before bedtime. This gives your body time to naturally increase melatonin production.
Use Built-in Blue Light Filters
Enable “night mode” or blue light filters on devices. These shift screen colors toward warmer, less disruptive tones. Set them to activate automatically at sunset.
Try Blue Light-Blocking Glasses
Look for glasses that block at least 90% of blue light in the 400-490 nanometer range for evening screen use.
Create Warm Evening Lighting
Replace bright overhead lights with dim, warm-toned lamps. Consider amber or red-tinted bulbs for bedside lighting.
Develop Screen-Free Bedtime Routines
Replace evening screen time with reading physical books, journaling, gentle stretching, meditation, or listening to calming audio content.
Building a Sleep-Friendly Environment
Create the darkest possible bedroom environment. Invest in blackout curtains and cover small LED lights on electronics. Keep your bedroom cool, quiet, and ideally technology-free.
Dr. Simmons emphasizes that small changes compound over time. Simple adjustments like using a traditional alarm clock instead of your phone and charging devices outside the bedroom can dramatically improve sleep quality.
For persistent sleep issues, contact the Encino Center for Sleep & TMJ Disorders at (818) 300-0070.
Technology as a Solution
While technology can cause sleep problems, it can also help when used thoughtfully:
- Screen dimming apps provide more control over blue light than basic settings
- Sleep tracking devices help identify patterns between device use and sleep quality
- Audio-only content, like meditation apps or sleep stories, avoids screen exposure
The key is being intentional—use airplane mode during wind-down periods and focus on audio-only features.
Transform Your Sleep with Encino’s Sleep Experts
Evening blue light disrupts your sleep by suppressing melatonin production, but simple changes can make a big difference: limit screen time before bed, use blue light filters, and create a dark sleep environment. You don’t need to eliminate technology—just be mindful about timing.
For persistent sleep issues, contact Dr. Simmons at the Encino Center for Sleep & TMJ Disorders at (818) 300-0070 for professional help with your sleep.