You’ve probably heard that the third Monday in January is the most depressing day of the year — but is Blue Monday real, or is it just another case of ‘fake news’?

The theory goes that ‘Blue Monday’ — the third Monday of the month, and the day many people return to work after the Christmas and New Year holidays — is the most depressing day of the year, according to an equation developed by Cliff Arnall, a former part-time tutor at Cardiff University.

Luckily, it’s complete nonsense.

Sure, you might be feeling a little down today — especially if, like me, this actually is your first day back at work after a great holiday — but you can’t blame it on ‘Blue Monday’.

The concept was popularised in 2005, after a press release from Sky Travel claimed to have calcuated the most depressing day of the year using weather conditions, debt level, the time since Christmas, the time since failing our New Year’s resolutions, low motivational levels and a ‘feeling of a need to take action’.

To lend credibility to the equation, the press release was published under Arnall’s name.

The concept of ‘Blue Monday’ took off, and Arnall continues to push the idea even now, more than a decade later — just today, The Telegraph ran a fresh interview with Arnall, “the expert behind the equation”, in which he claims that this could be the ‘Bluest Monday’ ever, due to anxiety about Donald Trump, Brexit, and the deaths of a number of popular celebrities in 2016.

But if you think it sounds like Arnall is pulling this stuff out of nowhere, you’re absolutely right.

In fact, Arnall didn’t even come up with the original Blue Monday equation.

In 2006, Guardian columnist Dr Ben Goldacre revealed that the largely pre-written Blue Monday press release had actually been shopped around to a number of academics by public relations agency Porter Novelli. Arnall was simply the first one to agree to be paid to put his name to it.

Aside from Blue Monday’s origins as a PR stunt, it’s also been pointed out by numerous people, including former Cardiff University neuroscientist Dean Burnett — a frequent critic of the Blue Monday ‘phenomenon’ — that the equation makes absolutely no sense on its own terms.

In 2013, Burnett memorably slammed the Blue Monday equation as “incorrect”, “unscientific”, “pseudoscientific”, “uberpseudoscientific”, “gibberish”, “bilge”, “rubbish”, “crap”, “stupid”, “utter bollocks” and “farcical” for attempting to combine variables like ‘time since Christmas’ with ‘weather conditions’.

“Even if you could combine these things, you’d get nothing useful,” Burnett wrote. “It’s like saying, ‘What do you get if you combine a) 14kg of sand, b) 53°C, c) 89 mph, d) A weasel’. At best, you’d get a hot fast sandy weasel, which would be of no use to anyone, but it might attract some media interest.”

Arnall himself has tried to distance himself from Blue Monday. Way back in 2010, he told The Telegraph — the same publication that just published an interview with Arnell about how this could be the most depressing Blue Monday yet — that people should “refute the whole notion of there being a most depressing day”, because it is “not particularly helpful”.

Blue Monday isn’t real, but of course, depression is — and it can affect you on any day of the year.

If you’re feeling down, mental health professionals are available at the beyondblue Support Service via phone 24/7 on 1300 22 4636 or via beyondblue.org.au/get-support/online-forums for online chat (3PM-12PM AEDT) or email responses (within 24 hours). You can also call the SANE Australia Helpline on 1800 18 7263 or visit sane.org. Further resources are available at blackdoginstitute.com.au and mindhealthconnect.org.au.