By now, you’ve probably heard that blue light from our screens can mess with sleep—and it’s true. Device screens emit large amounts of high-energy blue light (those short wavelengths in the visible spectrum), so it’s best to limit screen time at night—or at least reduce the amount of blue light they emit (more on that later). 

But blue light isn’t all bad. In fact, it plays a key role in setting our internal clock, our circadian rhythm, which affects everything from alertness and mood to hormones and metabolism. Bright, blue-enriched light helps us feel awake and energized during the day. The problem? When we’re exposed to that same light in the evening, it can seriously sabotage our sleep.

So, what color light is best for sleep?

The answer: red light.

Let’s dive into why red light is ideal at night—and how making a simple shift in your evening lighting can help your body wind down, naturally. Because when it comes to sleep, lighting can make all the difference.

The Science of Light and Sleep

The body’s circadian rhythm operates on a roughly 24-hour cycle, primarily guided by exposure to bright blue light. This rhythm is regulated by the brain’s suprachiasmatic nucleus (SCN), a region of the hypothalamus that receives information from light-sensitive cells in the eye.

When light—particularly light in the blue spectrum—enters the eye, it signals the SCN to suppress melatonin, the hormone that prepares the body for sleep. At the same time, it supports the release of cortisol, which promotes wakefulness and alertness. This system works well during the day, but at night, continued exposure to blue or bright white light can delay melatonin production and disrupt sleep onset and quality.

Why Blue Light Disrupts Sleep

Blue light is sleep-disruptive for the same reason you’re told to get natural sunlight first thing every day — it tells the body to wake up! 

Natural sunlight, device screens, and bright white or cool white color temperature LED bulbs are very high in blue light, and blue light wavelengths (especially around 480nm) signal your body to suppress melatonin your body to suppress melatonin, the hormone that prepares the body for sleep, while simultaneously increasing the release of cortisol, which promotes wakefulness and alertness.

Exposure to these wavelengths after sunset can delay your ability to feel sleepy and negatively affect your sleep overall. 

It’s also important to note that even light outside the blue range—if it’s bright enough—can affect melatonin release. This is why both color temperature and brightness matter when selecting evening lighting.

Best Colors for Sleep

It should come as no surprise, then, if blue light promotes wakefulness in the body, that red light (on the opposite side of the visible spectrum) enhances sleep. 

Why Red Light Is Better at Night

Red light wavelengths spanning 650-750nm will not suppress the release of melatonin. Any light bulb that doesn’t emit blue light is the best choice for use at night.

Red light helps create a more calming environment, helping cue the body and brain that it's time to wind down. 

Lighting Tips for Better Sleep

To support your natural circadian rhythm and promote better sleep, it’s important to adjust your lighting environment, especially in the evening. Minimize or eliminate sources of white light in the evening, such as device screens and overhead white lights. Keep the brightness of all light at a minimum. Any light, if bright enough, can keep you up!  

• Turn off overhead lighting Skip the overhead lights. Instead, use table or floor lamps with red or warm white bulbs.
• Use dim, warm lighting at night. The color temperature of light can give us a clue to which color its spectrum skews more towards - blue (energetic light that is awakening), or red (soothing light that won't suppress melatonin - the sleep hormone). Warm white color temperature lighting (2700K-3500K) skews more towards the orange/red light wavelengths, while daylight white/cool white (5000K and above) skews more towards the blue light wavelengths. We recommend using desk and floor lamps outfitted with warm white light bulbs ( anything 2700K-3500K ) or, our personal favorite - the Chromalux® 60W frosted bulb 

Best Low-Blue Light Bulbs to Use at Night

Any light that is "low blue" or low in blue lighting will be the best light bulb to use at night. Remember, the best light color to help you sleep is anything "warm" - whether that means warm white LED bulbs or any other technology with a color temperature below 2700K. 

We prefer using incandescent light bulbs at night, as they are the healthiest type of light and are naturally warm in color, with a spectrum that leans toward the red end.

If you're looking for specific options, here are a few Chromalux® favorites that check all the boxes:

• For recessed ceiling fixtures: Chromalux® R25 60W flood bulb
• For bedside lamps: Chromalux® B10 25W Low Wattage Light for Evening or A19 60W frosted incandescent bulbs

Best Red Light Bulb to Use at Night

The above light bulbs are dim and skew more towards the red end of the spectrum, making them very suitable for evening use. However, for optimal melatonin release and the best sleep possible, you should transition to completely red light bulbs 1-2 hours before bedtime.

The majority of red light bulbs for sleep are LED, and while that’s better than nothing, we strongly believe the natural, analog source of incandescence is always best, especially when winding down before bed. Red LED bulbs emit only red light but exhibit an unnatural, isolated spectral spike. In contrast, incandescent red light bulbs produce a smooth, gradual orange-to-red spectrum that extends into the infrared region.

Our red incandescent light bulb for sleep is the perfect light to use in bedside table lamps, bedrooms, bathrooms, or anywhere you spend your evening hours before bedtime. A lovely red, dim, purely analog incandescent light to help your mind and body unwind. 

When it comes to sleep and rest, there's no better light source than incandescent: this is the best red light bulb for sleep and bedrooms!

Other tips to support better sleep

• Get some sun every morning!

• Make sure you're well-lit during the day (bright light in the morning and daytime is another great way to set yourself up for a great night's sleep come nighttime — provided you use only low blue lighting and red light bulbs at night ;)

• Enable blue light filters on your devices. Device screens emit high levels of isolated blue light, but we all use them at some of the least ideal times, especially at night! Use specialized software (f.lux or Iris) or native display settings on your device to shift the screen toward warmer color temperatures and reduce the amount of blue light emitted. We wrote a guide on how to turn on the blue light filter on Mac + Windows, plus a cool trick to turn your iPhone screen red at night

• Sleep in a cool, completely dark room with no ambient lights from outdoor street lamps (use blackout curtains), and cover any electrical signal lights with tape. Even better, remove all electronics from your room…
• Turn off your WiFi before bed. Put your phone on Airplane mode, and keep it outside your room.
• Stop eating at least 2-4 hours before bed 
• Last but not least: relax! Journal, read, do anything to unwind from the day.

In Summary

• Bright, white light is best used in the morning and during the day to support alertness and regulate your circadian rhythm.
• In the evening, lighting should be dim and warm, avoiding cool white(blue-light-rich) sources of light.
• Red incandescent light is among the best options for nighttime use, as it minimizes circadian disruption and supports melatonin production. 
• Simple changes to your lighting environment can have a significant positive impact on sleep quality and overall health.

💡Help spread the light!

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