Do I use light therapy in the morning or evening for DSPD/ASPD?

When to use your device depends on your light therapy goals. But, in general, if you’re trying to advance your sleep phase (i.e. wake-up and sleep earlier), you should use your light therapy device in the morning, and vice-versa when it comes to delaying your sleep phase.

How many minutes at 10,000-lux to shift my schedule?

In general, bright light therapy sessions should last 20-30 minutes at 10,000 Lux. You can easily find out the distance you need to be from your device to get appropriate lighting by consulting our shop page.

Are glasses as effective as a light box for circadian issues?

Glasses tend to deliver lower light levels than lamps, but very consistently. You might need a week or two of gradually extending your sessions to see the same benefits, but, if your are too active for 30 minutes at a time sitting in one place, light therapy glasses may be the optimal solution for you.

Can melatonin be used with bright light therapy?

Whether or not to use melatonin—and when—depends on your light therapy goals. Melatonin generally builds up in the evening, preparing the body to go to sleep and stay asleep. For instance, if you’re trying to advance your sleep phase, you’ll want to consider using melatonin in the evening, to help get you to sleep earlier and stay asleep longer. If you’re interested in assessing your melatonin levels to figure out how best to combine it with your light therapy regimen, consult with a healthcare professional for advice on timing and dosage.

Is light therapy safe daily and UV-free?

Not only is bright light therapy safe for daily use, it’s strongly recommended. In fact, the number one best predictor of positive outcomes for users is consistency: making sure you use your bright light therapy product daily, at the same time, for the same amount of time, is the best way to ensure you see results. All our products are UV filtered with state-of-the-art acrylic panels, to ensure they emit no harmful radiation, and provide the safest possible experience.

How fast does it work for jet lag or shift work?

For serious clinical conditions like SAD, or shift work disorder it can take up to a couple of weeks to see results. However, most users will see results within just one week, depending on their goals. For instance, you can easily advance your sleep phase by about an hour a day just by using your bright light therapy product for 30 minutes every morning. So, even if you`re traveling to Europe, just one week’s worth of sessions prior to your departure should be plenty to see you wake up well-rested and -adjusted in your new time-zone.

Bright Light Therapy for Circadian Rhythm Disorders

The human body’s natural circadian rhythm (latin for circa, meaning ‘approximately’, and diem, meaning ‘day’) is set by retinal cells that use daylight as their zeitgeber (literally German for ‘time-giver’). In the evening, they signal dim-light melatonin onset (DLMO) to the brain, causing fatigue; in the morning, they signal melatonin break-down. Without their zeitgeber, these cells eventually offset the body’s clock from normal 24h days—sometimes by up to several hours.

Insufficient regular daylight breeds many health issues: advanced/delayed sleep phase disorder, shift-work disorder, and seasonal affective disorder. Thankfully, just 20-30 minutes of regular bright light therapy can effectively set your body’s internal clock, even when daylight isn’t regularly available. This essentially ‘hacks’ the circadian system—mimicking its natural zeitgeber and entraining it—to provide UV- and drug-free relief.

Timing at a Glance

	Morning		Evening
Lighting	Bright	Dim	Bright	Dim
Circadian effect	Retinal zeitgeber; can be used to advance sleep phase	Lack of natural zeitgeber delays sleep phase	Artificial zeitgeber; can be used to delay sleep phase	Maintain current sleep phase
Melatonin effect	Signals breakdown of overnight melatonin buildup	Overnight melatonin buildup persists longer	Later DLMO delays normal nightly fatigue	DLMO signals evening fatigue
Utility	Treats SAD, jetlag, SWD and DSPD		Treats jetlag, SWD, ASPD

Understanding Circadian Rhythm

Your Internal Clock (SCN) & Light Cues.

The light-sensitive ipRGCs (a type of light-sensitive cell) in your retinas are linked directly to the SCN: the brain area responsible for setting the body’s internal clock. When the ipRGCs respond to bright light in the environment, that message gets sent up to the SCN, signalling the body to either release or break down melatonin.

Phase Advance vs Phase Delay.

Knowing how this system operates, you can use light therapy to ‘hack’ it — either advancing or delaying the body’s circadian phase:

Bright light exposure in the early morning advances the circadian phase — akin to winding back the clock — waking you up earlier in the day, and helping you get to sleep earlier in the evening.
In the evening, bright light exposure instead delays the circadian phase — effectively setting the clock forward — letting you stay awake longer into the evening and wake up later the next day.

What Is Bright Light Therapy?

How It Works.

Ambient (indirect) sunlight is usually somewhere between 10,000 and 25,000 Lux. Naturally, specialized cells in your eyes respond to such bright white light by signalling your brain to break-down melatonin (the brain chemical promoting fatigue).

Artificially exposing these cells to bright enough light tricks your body into breaking melatonin down, by mimicking sunlight, effectively setting your body’s internal clock.

Safety & Comfort

Northern Lights products are ergonomically designed from the ground up to do just that. In just 20-30 minutes daily, our UV-free, neutral or blue-enriched white lights will provide 10,000 Lux glare-free artificial sunlight at a comfortable distance, which you’ll find listed on all our products.

Sit in front of your device at the recommended 10,000 Lux distance for 20-30 minutes, go about your normal routine, and you’re all set. Remember: you don’t even have to stare at the light—just sit in front of it with your eyes open. It’s really that simple.

How Light Therapy Helps Specific Circadian Issues

Delayed Sleep-Wake Phase Disorder (DSPD) occurs when the body’s clock remains set too far forward relative to daylight hours, delaying or prolonging sleep into the daytime. Basically, your body thinks it’s still 6am (and tries to keep you asleep) even if you’re already sitting at your office desk. In extreme cases, people can have serious difficulty just waking up before noon.

You can use morning bright light to anchor earlier wake times and, over time, synchronize your circadian rhythm to maintain a healthy sleep schedule.

Advanced Sleep-Wake Phase Disorder (ASPD) occurs when the body’s clock is set back earlier than normal daylight hours. Your body essentially thinks it should be wide awake and ready to go, even when it’s still 4am and you should still be asleep. This disorder makes it difficult to sleep until dawn, leading to fatigue early in the day. Evenings can also be problematic, as early fatigue can cause frequent headaches.

With careful timing, you can use evening bright light to delay melatonin onset—and therefore drowsiness—later into the evening. That way, you’ll set your body’s clock forward, to eventually align with normal nighttime sleepiness and morning wakefulness.

Shift Work Disorder (SWD) occurs frequently among those who work shifts that start and end at odd hours—specifically at odds with a normal sleep-wake schedule. Because there may be no sunlight to act as a natural zeitgeber for the body, routinely waking up and going to sleep can leave the circadian rhythm completely un-entrained. Eventually, work hours can be completely out of sync with the sleep-wake schedule, and out of sync with normal daylight hours.

Routinely timing bright light exposure before shifts, with the help of a healthcare professional, while also ensuring sleep in optimal conditions can help artificially set a circadian rhythm to match odd work hours.
You can do this by getting 10,000 Lux bright light therapy when you wake up for your shift, wearing blue-blocking glasses for an hour or two before going to sleep, and by making sure it’s completely dark in the room where you do sleep.

Jet Lag results from travel between time zones. When you travel east, your normal sleep-wake schedule will actually be phase-advanced relative to your destination. So, you should delay the sleep-wake cycle by an hour for each time zone you’re planning to cross (and vice-versa when traveling west). However, the body’s circadian rhythm can’t set itself forward by several hours within just a day or two, and that can leave you tired and out of sorts upon arrival.

Using light therapy sessions to either advance or delay the sleep wake cycle before and during travel can gradually tune the body to its new time-zone, even before arrival. As a guideline, it usually requires one light therapy session per day for each time-zone crossed.
In general, for each hour traveled east, waking up an additional hour later (and going to sleep an hour later) every day and using bright light therapy in the evening will delay the body’s sleep-wake cycle to match the destination’s daylight hours.
When going westward, instead, getting up and going to bed earlier each day—in combination with a morning light therapy regimen—will help advance the body’s sleep-wake cycle to fit the destination.

Whatever your body clock happens to need, keep in mind that mistiming light therapy sessions can in fact worsen your symptoms. So, when in doubt, consult your healthcare professional before adopting light therapy as part of your daily regime.

Choose Your Device

Boxelite Desk Lamp — robust 10,000-lux at desk; best for home/office routine.
Boxelite Desk Lamp OS-2 — variant option; similar use case.
Luminette 3 Glasses — wearable, hands-free morning exposure while commuting/reading.
AYO+ Glasses — wearable with app guidance; great for travel/shift schedules.
Sunelite Dawn Simulator — adjunct to ease wake-ups; pair with morning bright light for DSPD/jet lag.

How to Use Bright Light Therapy (Quick Start)

Starting a new regimen can sometimes feel daunting, but we’re absolutely sure that getting the most out of your bright light therapy products doesn’t require anything complicated. So, get started today, by following these 4 easy tips:

Duration: Your daily session should take 20–30 min, at the recommended 10,000 Lux distance (check the product page for details on your device).
Position: Keep your device at or above eye-level during your sessions. While you’ll need to keep your eyes open, you’ll never need to stare directly into the light either, so you can position it slightly off-center for the most comfortable light therapy experience.
Timing: Bright light therapy sessions are typically done within the first hour after you wake up. However, depending on your specific goals, you may want to schedule your sessions in the evening, before going to bed (See Timing at a Glance).
Consistency: To start with, just follow the recommended duration and distance (above), daily for the first week. If you’re not feeling its effects in that timeframe, you can extend them by 10 minutes going forward, or sit a few inches closer to your device. Once you’re feeling the effects for a week, all that’s left to do is maintain that same schedule.
Pairing: Maximize the benefit from your light therapy sessions by adopting a regular sleep schedule. If that feels complicated, consider getting your DLMO professionally tested, or adding melatonin to your light therapy regimen.

Safety & When to Seek Advice

Who should check with a clinician: we always advise consulting with a health professional as you embark on your light therapy journey. But, particularly users who take photosensitizing meds, who have photosensitizing health concerns (either dermal or retinal), or who have been diagnosed with bipolar disorder, severe insomnia, or depression should strongly consider consulting with a healthcare professional before using a light therapy device.
Mild effects: among other users, mild side-effects like eye strain, headache, or jitteriness may occur. If you’re experiencing any of these issues regularly, try adjusting the distance/duration/time of day that you use your device. And, of course, consult with your healthcare professional.
General: light therapy works best with UV-free, medical-grade devices like ours. Avoid bright light at hours that work against your light therapy goals. For instance, if you’re trying to advance your sleep phase, avoid evening bright light.