As another winter rolls around, like clockwork, the days get shorter, darker and colder.

And while many enjoy the change of seasons and look forward to Christmas, for others it can bring a sense of dread.

Seasonal affective disorder (SAD) - also known as ‘winter sadness’ - is a form of depression that comes and goes in patterns. According to NHS statistics, around one in 15 people in the UK experience this, usually anywhere between the months of September and April.

But why does this phenomenon occur year in and year out for many?

“It typically happens when the clocks go back, and we think one of the major factors in developing SAD is the reduced exposure to sunlight which we know is good for us,” explains Karen Lince, deputy clinical lead at Wellbeing Norfolk & Waveney.

According to the NHS, a lack of sunlight may stop a part of the brain called the hypothalamus functioning properly.

This in turn is thought to affect the production of melatonin, the hormone that makes you feel sleepy, and serotonin, the hormone that plays a pivotal role in your mood, appetite and sleep.

Those with SAD may find their body produces melatonin in higher levels than normal, and lower levels of serotonin which is linked to depression and feeling low.

A lack of sunlight can also affect the body's internal clock, also known as the circadian rhythm. Your body uses sunlight to time various important functions, such as when you wake up – therefore lower light levels during winter may disrupt your body clock and lead to SAD.

But what exactly are the symptoms of seasonal affective disorder?

“Essentially, the symptoms of depression,” explains Karen.

“You can expect to feel more tired and lethargic, and you may also notice your eating habits change, whereby you eat more food and crave carbs especially. You’ll also feel sad, tearful a lot of the time, lack energy and motivation, and find it hard to concentrate.”

Other common symptoms include feeling irritable; feelings of despair, guilt and worthlessness, feeling stressed or anxious, and a reduced sex drive.

“When we’re depressed, our thinking changes too. We’re more likely to feel bad about ourselves which in turn leads to low confidence, and we’re less likely to go out and do the things we normally enjoy doing. This then leads to a vicious cycle. But those who suffer from SAD only experience these feelings at a certain time of year.”

But don’t despair, as there are a number of remedies and steps that can be taken to help alleviate the symptoms of SAD.

“Get as much sunlight as you can at this time of year. Go on a walk at lunchtime, even if it’s overcast out and you need an umbrella, as you’re still getting some sunlight at least. Studies have shown that those who went for a walk everyday had a significant improvement in their mood compared to those who didn’t.”

Karen also suggests making your home as light and airy as possible during the autumn/winter season, as your surroundings can also have a huge effect on your mood and wellbeing.

“A lot of us are still working from home, so try to have your desk near the window, and open any windows where you can.

“In addition, diet also plays a key role in not just our physical health but our emotional wellbeing too,” she adds.

“Lower your alcohol intake, and swap out processed foods for fresh foods. Think protein, fruit and vegetables.”

However, if you feel these lifestyle changes aren’t helping, the next best course of action to take is to visit your GP for further help and advice.

“It can be quite difficult to get a diagnosis for SAD as you need to be seeing a pattern over some time, over the course of years. But with any depression, talking therapies are a great starting point. CBT-based therapies are what the National Institute for Health and Care Excellence (NICE) recommends, as it will help you understand and change those vicious cycles, and how best to manage symptoms of depression during winter time.”

Light therapy may also alleviate your symptoms on a short-term basis. Some studies have shown that light boxes, also known as SAD lamps, can improve a person’s mood considerably, especially if used for around 30 minutes to an hour each morning.

It does this by producing a bright light that safely stimulates the sunlight we miss during the darker months.

In more severe cases, antidepressants such as selective serotonin reuptake inhibitors (SSRIs) may be prescribed.

“It’s not uncommon to feel low at this time of year, especially during a pandemic. We all have mood changes in the winter, and tend to feel better in the summer. If you feel your mood drop, look after yourself. It’s important to respond to these changes by making small changes, and if it’s a worry, you should seek help and get in touch with your GP.”

To find out more about seasonal affective disorder and other forms of depression, wellbeingnands.co.uk