Why is it so hard to wake up in winter? Brehan Crawford, L.Ac., explaining the rule to wait for the sun before getting up

Why Is It So Hard to Wake Up in Winter?

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    If the alarm goes off in the dark all winter and getting out of bed feels like lifting a weight, your willpower is not the problem. Your body clock reads light, and the light is telling it the night is not over. Here is what Chinese medicine said about winter mornings 2,000 years ago, what the light research shows, and what to do tomorrow.

    The short answer

    It is hard to wake up in winter because your body is still in its biological night. Dark mornings and dim days leave your internal clock running late, so the alarm rings before your body has switched to daytime. The oldest text in Chinese medicine says to go to bed early in winter and wait for the sun before getting up. The modern version is the same idea: get bright light soon after you wake, outdoors if you can, from a 10,000 lux light box if you cannot.

    The short version, on video.

    Why is it so hard to wake up in winter?

    Because the signal your body uses to end the night arrives late, or not at all. Morning light is what tells your internal clock the day has begun. In winter the sun comes up after the alarm does, so you are asking your body to start its day in the middle of its night.

    Researchers at the University of Colorado Boulder showed how closely the clock follows the season. After a week of living by natural winter light alone, 9 hours 20 minutes of light and 14 hours 40 minutes of dark, people’s biological night began earlier than it did under electric lighting, and it ran longer than in summer. In the modern lit environment, their clocks were timed later in winter and summer alike.[1]

    In some people the long winter night shows up in the blood. A team at the National Institute of Mental Health sampled melatonin every 30 minutes for 24 hours in 55 people with seasonal affective disorder and 55 matched volunteers, once in winter and once in summer. In the patients, the nightly stretch of melatonin secretion lasted 9.0 hours in winter and 8.4 hours in summer. In the healthy volunteers it did not change.[2]

    A long biological night on a clock that runs late is still going when the alarm rings. That is the weight you feel on a January morning.

    Daylight is what pulls the clock back. In an analysis of more than 400,000 adults in the UK Biobank, each additional hour a person spent outdoors in daylight was associated with greater ease of getting up in the morning, less frequent tiredness and lower odds of low mood.[3] The same clock is the reason it is better to eat earlier in the day. Rhythm is terrain, the daily conditions your body is working in, and it is the work we do together inside Gut Brain Synchrony.

    Do you need more sleep in winter?

    Chinese medicine says yes, and it said so about 2,000 years ago. The Su Wen, the foundational text of Chinese medicine, gives sleep instructions for each season. In spring and summer, go to bed late and get up early. In autumn, go to bed early and rise with the rooster. Winter is the only season in which it tells you to rise late: go to bed early, and wait for the light of the sun before getting up. If you are getting up in the dark all winter, you are breaking one of the oldest rules in Chinese medicine, and it may be part of why winter drags you down so hard.

    The reasoning is in the name the text gives the season. The three months of winter are called closing and storing. Water freezes, the ground cracks, and the instruction is not to disturb the yang, the warm, active, outward-moving side of your physiology. Winter belongs to the Kidney, the organ system that holds your deepest reserves. Getting up into cold and darkness spends those reserves in the season meant for banking them. The text is specific about the cost: go against winter and you injure the Kidney, and you arrive in spring with little to grow on.

    There are signs the body keeps this calendar even in a city. A Berlin sleep clinic ran overnight sleep studies on 188 patients through 2019, with alarm clocks not allowed. REM sleep ran about 30 minutes longer in winter than in spring. Total sleep ran up to an hour longer in winter than in summer, though that difference was not statistically significant. These were patients with disturbed sleep, and the authors wrote that if the pattern holds in healthy sleepers, it would be the first evidence that sleep habits need to change with the season.[4]

    So wanting more sleep in winter is not laziness. Go to bed earlier. And when you cannot wait for the sun, because work and school start when they start, bring the light to you.

    Why do I feel so tired in winter?

    Because you are living in the dim, and the days you stay indoors are the dimmest. Your eyes adapt so well that a lit room and an open sky feel similar. A light meter says otherwise.

    How dim is indoors?

    When researchers in India took a lux meter to nine outdoor and four indoor locations, the median indoor reading was 179 lux. An open playground read 9,300 lux, about fifty times brighter. Cloud did not change the picture: neither weather, season nor time of day moved a location from above 1,000 lux to below it. What did matter was open sky. Spots hemmed in by buildings read like indoors.[5]

    How little bright light we get in winter

    When 12 young adults in Montreal wore light sensors in summer and in winter, they spent 2.6 hours a day in bright light, above 1,000 lux, in summer. In winter it was 0.4 hours. Even in summer, more than half of their waking day was spent below 100 lux.[6] On the days you do not leave the house, you are barely getting real light at all.

    What light does to brain chemistry

    Light is more than a clock signal. Researchers in Melbourne sampled blood from the internal jugular vein, the vein that drains the brain, in 101 healthy men. Serotonin turnover in the brain was lowest in winter, and the rate of serotonin production tracked the prevailing hours of bright sunlight, rising rapidly as the light increased.[7]

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    Does light therapy work for seasonal depression?

    Yes, and doctors have relied on it for winter depression since the 1980s. In 1984 Norman Rosenthal and his colleagues described 29 patients whose depressions returned every year with oversleeping, overeating and carbohydrate craving. In the 11 who tried it, extending the day with bright artificial light had an antidepressant effect.[8]

    A meta-analysis of 19 randomized trials found bright light superior to placebo for seasonal affective disorder, with patients 42 percent more likely to respond to the real light than to a dim or sham one.[9] An earlier meta-analysis in the American Journal of Psychiatry put the effect of bright light in the same range as most antidepressant drug trials, and found dawn simulation effective as well.[10] A dawn simulator is a bedside light that brightens gradually before you wake. It is the Su Wen’s instruction built into a lamp.

    The head-to-head comparison came from Canada. Across three winters, 96 patients with winter depression received either 30 minutes of 10,000 lux light each morning or the antidepressant fluoxetine. After eight weeks, 67 percent of each group had responded, and the light group had improved more by the end of the first week.[11]

    Why morning light matters most

    Timing is where the trials meet the old rule. Researchers at Oregon Health Sciences University gave 51 patients bright light either from 6 to 8 in the morning or from 7 to 9 in the evening. Morning light pulled the body clock earlier and lifted mood more than evening light, which pushed the clock later. Their recommendation was to schedule bright light immediately on awakening.[12]

    A placebo-controlled trial of 96 patients, published alongside it, counted responses by a strict standard: 61 percent with morning light, 50 percent with evening light and 32 percent with placebo. Average depression scores did not differ between the groups at four weeks, and the edge over placebo took at least three weeks to appear, so give it time.[13]

    Is daylight as good as a light box?

    The trial that tested daylight did not put it up against a full-strength box, but against a weak one it won clearly. In Basel, patients with seasonal affective disorder spent one week on either a daily one-hour morning walk outdoors or a low dose of artificial light that served mainly as a placebo. Half of the walkers were in remission at the end of the week, against a quarter of the comparison group. The walk also moved their melatonin rhythm earlier and lowered their morning cortisol.[14]

    That is why I send you outside first. The old text and the trials arrive at the same place: do not start your day in the dark.

    How to beat the winter blues at home

    01 Measure your light. Grab a free light meter app. Check your living room, then step outside and watch the number jump.
    02 Get into real daylight within an hour of getting up. Every day. It can be as simple as sitting on the porch with a warm cup of tea. Sit where you can see open sky.
    03 Do it when it is overcast. This works under cloud. A gray sky still reads far brighter than a lit room.
    04 If you cannot get outside, set up a 10,000 lux light box. Use it for 30 to 45 minutes in the morning. Studio lights work well for this. Hold your meter app where your face will be, so you know what is reaching your eyes.
    05 Go to bed early. The winter rule has two halves. An earlier night makes a bright morning possible.

    Start with tomorrow morning. For the evening half of the rhythm, Gut Health Basics: Your Sleep covers how to set up the night.

    Winter blues questions, answered

    What is the difference between the winter blues and SAD?

    Degree. Seasonal affective disorder is the far end of a spectrum most of us are on. In a telephone survey of households in Montgomery County, Maryland, 92 percent of people noticed seasonal changes in their mood and behavior, and for 27 percent those changes were a problem. Between 4.3 and 10 percent, depending on the definition used, reported impairment on the level of patients with the disorder.[15]

    Does red light therapy help winter blues?

    Not as well as white light. A 2025 network meta-analysis of 17 randomized trials and 773 patients ranked white light most effective for seasonal affective disorder, followed by green, then blue, with red light last.[16] For winter mood, what you want is brightness: daylight, or a bright white box.

    How long should you sit in front of a light therapy lamp?

    Thirty minutes at 10,000 lux, in the morning, is the dose the Canadian trial used.[11] I suggest 30 to 45 minutes. Sooner after waking is better than later.

    Winter is for storing. Go to bed early, and meet the light when it comes.

    — Brehan Crawford, L.Ac.

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    References

    1. Stothard ER, McHill AW, Depner CM, et al. Circadian Entrainment to the Natural Light-Dark Cycle across Seasons and the Weekend. Curr Biol. 2017;27(4):508-513. doi:10.1016/j.cub.2016.12.041
    2. Wehr TA, Duncan WC, Sher L, et al. A circadian signal of change of season in patients with seasonal affective disorder. Arch Gen Psychiatry. 2001;58(12):1108-1114. doi:10.1001/archpsyc.58.12.1108
    3. Burns AC, Saxena R, Vetter C, Phillips AJK, Lane JM, Cain SW. Time spent in outdoor light is associated with mood, sleep, and circadian rhythm-related outcomes: A cross-sectional and longitudinal study in over 400,000 UK Biobank participants. J Affect Disord. 2021;295:347-352. doi:10.1016/j.jad.2021.08.056
    4. Seidler A, Weihrich KS, Bes F, de Zeeuw J, Kunz D. Seasonality of human sleep: Polysomnographic data of a neuropsychiatric sleep clinic. Front Neurosci. 2023;17:1105233. doi:10.3389/fnins.2023.1105233
    5. Bhandary SK, Dhakal R, Sanghavi V, Verkicharla PK. Ambient light level varies with different locations and environmental conditions: Potential to impact myopia. PLoS One. 2021;16(7):e0254027. doi:10.1371/journal.pone.0254027
    6. Hébert M, Dumont M, Paquet J. Seasonal and diurnal patterns of human illumination under natural conditions. Chronobiol Int. 1998;15(1):59-70. doi:10.3109/07420529808998670
    7. Lambert GW, Reid C, Kaye DM, Jennings GL, Esler MD. Effect of sunlight and season on serotonin turnover in the brain. Lancet. 2002;360(9348):1840-1842. doi:10.1016/s0140-6736(02)11737-5
    8. Rosenthal NE, Sack DA, Gillin JC, et al. Seasonal affective disorder. A description of the syndrome and preliminary findings with light therapy. Arch Gen Psychiatry. 1984;41(1):72-80. doi:10.1001/archpsyc.1984.01790120076010
    9. Pjrek E, Friedrich ME, Cambioli L, et al. The Efficacy of Light Therapy in the Treatment of Seasonal Affective Disorder: A Meta-Analysis of Randomized Controlled Trials. Psychother Psychosom. 2020;89(1):17-24. doi:10.1159/000502891
    10. Golden RN, Gaynes BN, Ekstrom RD, et al. The efficacy of light therapy in the treatment of mood disorders: a review and meta-analysis of the evidence. Am J Psychiatry. 2005;162(4):656-662. doi:10.1176/appi.ajp.162.4.656
    11. Lam RW, Levitt AJ, Levitan RD, et al. The Can-SAD study: a randomized controlled trial of the effectiveness of light therapy and fluoxetine in patients with winter seasonal affective disorder. Am J Psychiatry. 2006;163(5):805-812. doi:10.1176/ajp.2006.163.5.805
    12. Lewy AJ, Bauer VK, Cutler NL, et al. Morning vs evening light treatment of patients with winter depression. Arch Gen Psychiatry. 1998;55(10):890-896. doi:10.1001/archpsyc.55.10.890
    13. Eastman CI, Young MA, Fogg LF, Liu L, Meaden PM. Bright light treatment of winter depression: a placebo-controlled trial. Arch Gen Psychiatry. 1998;55(10):883-889. doi:10.1001/archpsyc.55.10.883
    14. Wirz-Justice A, Graw P, Kräuchi K, et al. ‘Natural’ light treatment of seasonal affective disorder. J Affect Disord. 1996;37(2-3):109-120. doi:10.1016/0165-0327(95)00081-x
    15. Kasper S, Wehr TA, Bartko JJ, Gaist PA, Rosenthal NE. Epidemiological findings of seasonal changes in mood and behavior. A telephone survey of Montgomery County, Maryland. Arch Gen Psychiatry. 1989;46(9):823-833. doi:10.1001/archpsyc.1989.01810090065010
    16. Wan Y, Ding J, Fan M, Huang H. Effectiveness of visible light for seasonal affective disorder: A systematic review and network meta-analysis. Medicine (Baltimore). 2025;104(27):e43107. doi:10.1097/MD.0000000000043107