If you believe in it, Blue Monday is here and for many can be the most depressing day of the new year so far - or so the theory goes.

The weather, bills and demise of new year resolutions all contribute towards this apparently - although it could be a case of the winter blues.

What is Blue Monday?

Supposedly, it's a day - Monday - in January when many people may be feeling fairly miserable, thanks to the longer stretch between pay days, the lull after the festive period and getting back to the 9-5 grind.

A few years ago a university professor managed to precisely calculate this day as the most depressing of the year using the following factors, including: weather conditions, debt level (the difference between debt accumulated and our ability to pay), time since Christmas, time since failing our new year’s resolutions, low motivational levels and feeling of a need to take action.

However, he was asked to come up with this formula by Sky Travel...

The phrase 'Blue Monday' is now used by PR and marketing firms to sell uplifting deals designed to make you feel better.

When is it?

This year, the day falls on Monday, January 20.

Does it really exist though?

If you're cynical, no, not really. However, winter generally can lead to symptoms of depression in some people, and it might be a good time to actually consider your health and mental health if you have been feeling low.

What do the experts say?

According to mentalhealth.org.uk there can be seasonal variations in our mental health.

Some people might be experiencing Seasonal Affective Disorder with symptoms of depression that come and go in a seasonal pattern (and are usually more intense in the lower light months). Bodily changes in the winter can affect our hormones and impact our sleeping and eating habits, and our mood.

Rosie Weatherly, Information Content Manager at Mind, said: “Blue Monday’ is a slogan from an advertising campaign, and there is no evidence to suggest one specific day increases the risk of experiencing depression.

"‘Blue Monday’ is unscientific, and trivialises depression - which in reality is a potentially life-threatening condition.

"The winter months can cause us to feel low, potentially as a result of shorter days, changes in weather or money worries. These things might contribute to some people’s depression, but not others, and people with depression will be affected for more than one day.

What can we do to help ourselves?

Things that are known to be good for our mental health such as exercising and spending time in green and blue spaces are harder to do when the days are short and nights are long. Do things that make you feel good.

January can be a time of deprivation for many, thanks to the relentless call for diets, hardcore exercise regimes and extreme weight loss measures.

Don't be too hard on yourself. 

Mind say: "If you’re finding things hard in January, there are lots of things you can try to improve your mental wellbeing.

"Getting outside during daylight can often help, as can doing some exercise.

"Focussing on a hobby like cooking, crafting or climbing can also give us an enjoyable break from day to day pressures. The important thing is to find something that works for you, because we are all different."

It may be that you use 'Blue Monday' to treat yourself to something - don't feel guilty about this either.

Let us know what you think of Blue Monday - and any suggestions you can give to people feeling a bit low.