About 2 million people in the UK, and 12 million across northern Europe, are thought to have the “winter blues”, a form of depression characterised by low mood, fluctuations in appetite and heavy sleeping, which peaks in January and February each year. So, how should you go about tackling it?

Exercise

The simplest means of beating the winter blues is to force yourself to stay active, even when it’s dark and cold. Research has shown that even a 15-minute walk in the middle of the day is enough to increase crucial neurotransmitters, such as dopamine and norepinephrine, which help energise the brain and regulate circadian rhythms. If you can exercise earlier in the day, absorbing natural daylight within two hours of waking up, it will be even more beneficial.

Get into the right mindset

Scandinavian nations, such as Denmark, which endure some of the longest and bleakest winters on the planet, embrace that much-discussed concept of hygge. The ethos is to embrace winter as a time to slow down, enjoy being at home, and spend time inside with friends and family. You can also improve your mood by using this time to plan things to look forward to later in the year. Studies have even found that many people who enjoy travelling get more pleasure from anticipating the holiday than from the trip itself.

Eat complex carbohydrates

Greasy, refined carbohydrates such as pizza and garlic bread give you short-term pleasure, but will make you feel more sluggish over the winter months. More complex carbohydrates, such as broccoli, spinach, courgettes and lentils take longer to digest, meaning they don’t cause the sudden spikes in blood sugar that can play havoc with your mood.

Take fish oil and vitamin D supplements

Vitamin D plays a role in regulating mood, maintaining optimum blood sugar levels and boosting our immune systems, but one of the main natural sources of vitamin D is sunlight. This means that a large proportion of the UK population are deficient in vitamin D during the winter months. One study found that when adults with the winter blues were given 400-800 international units of vitamin D3 a day, their mood improved substantially. Omega-3 supplements may also be beneficial. Iceland is one of the northernmost nations in the world, but has the lowest rates of the winter blues. One reason for this is thought to be their high consumption of fish, such as salmon and cod, which are rich in omega-3 polyunsaturated fatty acids. Omega-3s are thought to exert an antidepressant effect by improving the functioning of cells in the brain and blood.

Meditate

Dr Norman Rosenthal, the psychiatrist who first began researching the winter blues, is a firm believer of transcendental meditation as a means of treating the condition. Studies have suggested that by relaxing the body and mind through stimulating the release of the hormone melatonin, meditation can lead to increased activity in the left prefrontal cortex, a part of the brain associated with happiness, and decreased activity in brain regions linked to stress.

Try light therapy

Research has shown that between 50% and 80% of people who get the winter blues can get either partial or complete relief from bright light therapy, applied by sitting near a light box for half an hour a day through autumn and winter. It is important to use ultraviolet-filtered light units, as it can be harmful for people to use a normal light in this way, and some research suggests that light boxes which are enriched in light towards the blue end of the spectrum are most beneficial. This is because blue light suppresses the hormones which make you fall asleep at night, enabling people to get their day started earlier and avoid depressogenic oversleeping.

Take tryptophan supplements

The effectiveness of light therapy can be enhanced by combining it with a tryptophan supplement, an amino acid which gets converted to serotonin in our body. Serotonin is a neurotransmitter that regulates happiness and mood, and its levels are typically thought to be reduced in people who suffer from winter blues. Some studies have suggested that tryptophan can be as effective for some forms of depression as antidepressant medications.

Seasonal affective disorder, or Sad, a more pronounced form of depression in winter, should be dealt with by a qualified professional. Read the NHS website for more information.