The dark half of the year and melatonin

Family Health Diary

We are past the shortest day (22 June). The days are getting longer and it is great to see daylight on the way to work (on fine days). In winter some people say they feel a bit down. Some researchers say that ‘seasonal affective disorder’ (SAD) is a thing and others say it is not. What we do know is that melatonin makes us sleep and we produce more melatonin in winter.

Our bodies are designed to be awake during the day and to sleep at night. We produce a natural chemical in our bodies called melatonin. This helps us to sleep. When we are exposed to light we stop producing it and our bodies know it is time to wake up.

Our bodies respond to sunlight or strong artificial light. This is why we are told to not be in front of screens or strong artificial lights when we are getting ready for bed. Our body needs to know it is getting darker so it starts winding down for sleep. Conversely we need plenty of light during the day so our body knows to be awake. This can be a challenge in winter. If you are exposed to daylight or very bright artificial light in the morning, your body not only wakes up, it will also more easily produce melatonin (and therefore sleep) at night.

We all know that sleep itself is restorative, but so is melatonin. Melatonin not only makes you sleep it also sets the pace of our body. It helps fight infection, inflammation, cancer and autoimmune diseases. Our body produces more melatonin in winter because the days are shorter and the nights are longer. Our body is trying to sleep more in winter and yet most of us set the alarm for the same time and start work at the same time winter and summer. It is this pushing back against nature that may be the cause of feeling lethargic in winter.

You might have heard of serotonin. This is a naturally produced chemical just like melatonin. In fact our body makes serotonin into melatonin. Our body mainly only makes serotonin during the day and at night when it gets dark we turn it into melatonin. In summer we produce more serotonin and in winter we produce more melatonin. Serotonin makes us feel positive, calm and focussed. Melatonin makes us sleep and restores our immune system. So our body is trying to be happy and busy during the longer days and slower and sleepier during the darker days.

The effect of natural light from being outside on a summer day can be a thousand times more than artificial lights inside. So even in winter; if you work inside try and go outside for a break during the day. You will be surprised at how much better you feel (due to increased serotonin production). This is also why we should all sleep in as close to total darkness as possible so we produce sufficient melatonin to sleep well.

Most of us sleep better in winter due to the lower light levels, but if you are having trouble sleeping, talk to your pharmacist about melatonin. If you are 55 or older and meet certain criteria a pharmacist might be able to sell you a short course of melatonin if you are having trouble sleeping. This will require a consultation with the pharmacist which will take several minutes. If you are feeling a bit slow and sluggish in winter, be kind to yourself, you have less serotonin in winter. Get more rest, it’s what your body is trying to get you to do. That’s why people do ‘spring cleaning’ with all that energy, and not ‘winter cleaning’ when we are feeling tired. Remember when you sleep and produce melatonin it is also helping your immune system. Sleep really is restorative for our body and it makes us more awake and happy during the day. Wishing you all the best for winter wellness.

Written by Linda Caddick

This blog provides general information and discussion about medicine, health and related subjects. The information contained in the blog and in any linked mate­ri­als, are not intended nor implied to be a substitute for professional medical advice.

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