Like any other season, winter brings its positives as well as challenges to a healthy sleep routine. Short days and long nights can make for cozy, quiet, as well as restful evenings. For many of us the quick pace of autumn seems to quieten down a little, once winter hits, helping us to slow down and relax But, as with so many things, there are a few pitfalls that we should be on the look-out for.
Extended periods of darkness lead to changes in circadian rhythms, which can throw our sleep routines off course, and leave us feeling sluggish, with low-energy levels, and, despite a long night’s sleep, simply tired. Millions of people, particularly those in the Northern Hemispheres, experience something called Wintertime Seasonal Affective Disorder, which can have a significant negative impact on sleep and mood, as well as appetite and energy levels, particularly when exercising.
What is the key to sleeping well in winter? Know what shifts and changes in your sleep pattern to look out for. Be aware of your daily habits — both good and bad — which may be affecting your ability to rest at night.

Below are Dr Breus’ tips for a healthy night’s sleep, even during the winter months;

• Seek out sunlight (or any light): This might be the most important tip on this list. Exposing yourself to light during daylight hours is crucial to sleeping and feeling well throughout winter. Light exposure first thing in the morning inhibits melatonin production and stimulates cortisol. These hormonal changes are a key element of the get-up-and-go response we all want to have in the morning, as opposed to the sluggish feeling that often accompanies the start of a winter’s At midday, the sun is the strongest—that’s another good time to get a dose of sunlight if you can. Soaking up light during the first part of the day will help your energy levels, mental function and lift your mood. It will also send powerful cues to your bio clock, helping to keep it in sync and on track. This in turn will translate into having an easier time falling asleep at night, and more refreshing, restorative rest.
  If there is little sun outside or you have difficulties getting outside during the daytime, due to work or other commitments, use bright indoor lights. This will also help stimulate your wakefulness during the morning and midday and act as a supplement or an alternative to natural light. If you’re someone who experiences depression or seasonal affective disorder in winter, consider light therapy to help your sleep and mood.
• Don’t wind down too early. We all know that the days are much shorter in the winter, depending on where you live. The further up north, the shorter the days and the less sunlight, if any at all, there is. The decrease of daylight means big changes for our bodies, which rely on light and darkness cues to regulate our bio clocks. This includes the production of melatonin, a key hormone facilitating sleep. With so much time spent in darkness, melatonin production—which is triggered by the absence of light—becomes extended. The body may begin winding down earlier in the evening and many of us seem to go to bed earlier and stay in bed longer during the winter months. But your sleep and health are best served by sticking to your standard (hopefully consistent!) routine of sleep, rather than extending your sleep time in the depths of winter.
• Keep up with exercise: This is an evergreen tip for sleep. There’s no time of year when exercise and physical activity isn’t a good thing for your nightly rest. But exercising during the winter months can be particularly helpful for healthy A regular exercise routine can help strengthen your circadian rhythms, which will keep you sleeping, eating, and feeling more like yourself during the winter months. Timing your exercise right during winter can expand its benefits even further. If you’re struggling to get moving in the mornings, try a workout first thing. Even a short one can make a big difference to your day. If you’re finding yourself tempted to crawl into bed right after dinner, consider scheduling exercise for the very late afternoon or early evening. This will send a message to your bio clock and body that it’s time to keep alert and active for another few hours.
• Know your Vitamin D: Our most potent source of Vitamin D? Sunlight. That’s why so many people—especially those in northern areas of Europe—suffer from low levels of Vitamin D during the winter. Some studies show that up to 50 percent of adults and children have a Vitamin D deficiency during the winter months.

Research has shown that in addition to its other benefits for health (stabilising mood, supporting healthy bones and strengthening immune function), Vitamin D also enhances sleep. Studies show a lack of Vitamin D reduces sleep time and lowers sleep efficiency, which is an important measurement of sleep quality. For many people, winter is the time we’re most likely to be deficient.

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