Use light to improve mood and energy

Lack of light can cause seasonal depression. Help combat it with light therapy.

The impact of light on your body

Light is needed for vision, but light entering our eyes also has other “non-image forming” effects. It plays an important role in how we feel and how well we can function mentally. Reduced sunlight in winter may cause winter-onset SAD (seasonal affective disorder) or seasonal depression.

Some of the non-image forming effects of light exposure depend on the colour of light in combination with timing of exposure. Some colours and intensities that are beneficial at one time of day may be detrimental at other times of day. For examples, blue light, which is emitted by the sun during the day, is good at keeping us awake and energetic so can be used to help combat seasonal depression.

Light therapy for waking up

Wake-up lights

In nature, daily life is initiated by the sunrise, and comes to rest after sunset. Modern society calls for different schedules, so we often need to get up before sunrise, and continue activities till long after sunset.

However these natural, gradual changes from dark to light and back to dark are important cues for our body’s optimal function and for our sense of wellbeing. Wake-up lights provide a gradual increase of light intensity before you wake up that gently preparing your body, so you can have a more energized feeling and natural, easy rising.

Light therapy for sleeping

Sleep patterns

In modern society we have the capability to prolong the light part of the day by using artificial lighting. Our bodies are not synchronized to the rhythm of the sun, but to our lifestyle. Many people are extending their daily activities towards the evening, delaying their bedtime and, in case of work or school obligations on the next day, shortening their sleep time.

However, not enough sleep has an impact on our daily functions. Sleep & Wake-up Lights let you reduce the amount of light during the last few hours before bedtime by simulating a natural sunset, and help you wind down with light-guided breathing.

By maintaining routine sleep and waking times with fewer variations, sufficient light exposure during the day, low light exposure during the evening and darkness during the night, one can achieve a good balance between rest and activity and reduce a variety of health risks.

£189.99*
SmartSleep Wake-up light with night-time function

HF3651/01

Simulated sunrise and sunset

RelaxBreathe to sleep

Multiple lights and sounds

Midnight light
4.2 (27 reviews)

Overall rating 4.2 / 5
View product
£105.00*
Philips SmartSleep Wake-up light: sunrise alarm clock with 2 sounds

HF3505/01

Wake up with light

2 natural sounds

FM radio and Bedside lamp
4.1 (52 reviews)

Overall rating 4.1 / 5
View product

Proven results: Selected studies

Winter blues
Winter blues

Research on Winter Blues

Avery, D. H. et al. Bright light therapy of subsyndromal seasonal affective disorder in the workplace: morning vs. afternoon exposure. Acta Psychiatrica Scandinavica 103, 267–274 (2001)

This study compared the two Philips energy lights, blue vs white, both 20 minutes per day for one week (5 mornings at home).

There was no difference in the efficacy of the two treatments found, the response rates were the same. One week after the latest treatment the condition of the users improved further compared to the last therapy day.

Duijzer, W. & Meesters, Y. The Effects of Low Intensity Monochromatic Blue Light Treatment Compared to Standard Light Treatment in Sub- syndromal SAD; SLTBR Abstracts 2011, p.34
Day light and energy
Day light and energy

Research on day light and energy

145 healthy participants have used Philips EnergyLight (2500 lux) for at least 1 hour per day and at least 5 days per week at their workplace during 2 (out of 4) of 4-week periods (the other 2 4-week periods they used no extra light at their workplace).

Even for the participants with no seasonal variation of mood and energy the bright light exposure has improved vitality and mood when compared to the weeks without extra light.

Partonen, T. & Lönnqvist, J. Bright light improves vitality and alleviates distress in healthy people. Journal of Affective Disorders 57, 55–61 (2000).

This laboratory study compares the effects of bright light exposure (5000 lux) during the daytime and nighttime on different psychological and physiological measures.

Whereas the impact the bright light has on different bodily functions varies depending on the part of the day, the effect of counteracting tiredness is universal during day and night.

Rüger, M. Time-of-day-dependent effects of bright light exposure on human psychophysiology: comparison of daytime and nighttime exposure. AJP: Regulatory, Integrative and Comparative Physiology 290, R1413–R1420 (2006)

Viola, A.U. et al. Blue-enriched white light in the workplace improves self-reported alertness, performance and sleep quality. Scand J Work Environ Health 34, 297–306 (2008)
Waking up by light
Waking up by light

Research on waking up by light

The paper describes two sub-studies with Philips Wake-up Lights, evaluating (A) 2 week usage at home against waking up without light and (B) 2 week usage at home of different light intensities of the gradually increasing light (0 lux, 50 lux, and 250 lux).

The main results from both groups confirm that waking up with gradually increasing light prior to the alarm time is of overall better quality than without light, the energy level of the users at wake-up is improved, participants reported easier rising, better mood, productivity, and quality of social interactions. A transient period of grogginess after awakening, called sleep inertia, was reduced when participants used Wake-up Light.

Gimenez, M. C. et al. Effects of artificial dawn on subjective ratings of sleep inertia and dim light melatonin onset. Chronobiology International 27, 1219–1241 (2010)

In how far can the effects of Wake-up Light be attributed to the gradually increasing light before the alarm time, and in how far it is the fact that the light is on when the eyes go open, was the central question of this controlled sleep laboratory study.

It has shown that the alerting and activating effects are mainly linked to the gradual increase of light while the user is still asleep and that these effects can directly be sensed during the first use. Several physiological measures, such as skin temperature change at and after the wake-up follow the alerting dawn signal. Sleep recordings demonstrate that during the gradually increasing light period the users spend more time in the awake state prior to finally waking up then when they are spending the last 30 minutes of their sleep in darkness.

On the average they finally woke-up only 2 minutes earlier than with the sound alarm only, but feeling more ready to wake-up.

Van de Werken, M. et al. Effects of artificial dawn on sleep inertia, skin temperature, and the awakening cortisol response. Journal of Sleep Research 19, 425–435 (2010)

In how far can the effects of Wake-up Light be attributed to the gradually increasing light before the alarm time, and in how far it is the fact that the light is on when the eyes go open, was the central question of this controlled sleep laboratory study.

It has shown that the alerting and activating effects are mainly linked to the gradual increase of light while the user is still asleep and that these effects can directly be sensed during the first use. Several physiological measures, such as skin temperature change at and after the wake-up follow the alerting dawn signal. Sleep recordings demonstrate that during the gradually increasing light period the users spend more time in the awake state prior to finally waking up then when they are spending the last 30 minutes of their sleep in darkness. On the average they finally woke-up only 2 minutes earlier than with the sound alarm only, but feeling more ready to wake-up.

Van de Werken, M. et al. Effects of artificial dawn on sleep inertia, skin temperature, and the awakening cortisol response. Journal of Sleep Research 19, 425–435 (2010)

Wake-up Lights were used in a study with adolescents, 103 pupils between 7 and 18 years old.

During the week they used Wake-up Light, pupils awoke earlier, felt more alert at awakening, got up easier and reported a higher alertness during the second lesson at school, compared to the week when they used their habitual way of waking up. Evening types benefited more than morning types, but the improvement was there for the group as a whole as well.

Fromm, E. et al. Evaluation of a dawn simulator in children and adolescents. Biological Rhythm Research 42, 417–425 (2011)

Use light to improve mood and energy

The impact of light on your body

Light therapy for waking up

Wake-up lights

Light therapy for sleeping

Sleep patterns

SmartSleep Wake-up light with night-time function

Philips SmartSleep Wake-up light: sunrise alarm clock with 2 sounds

Proven results: Selected studies

Research on Winter Blues

Research on day light and energy

Research on waking up by light