A drinks company has claimed that Blue Monday, usually in the third week of January, is actually today. But 'the most depressing day of the year' is a myth that has no basis in science

Every year, towards the end of January, we’re subjected to a particularly annoying and persistent form of bullshit in the national news known as "Blue Monday". It first cropped up in 2005, when psychologist Cliff Arnall produced a formula that claimed to show which was the most "depressing" day of the year. By mushing together obvious things such as weather conditions, debt, the amount of time since Christmas, and the fact that we all hate Mondays (because of work), Arnall decided that it should crop up on the third Monday of January, or thereabouts.

It’s a complete load of rubbish, of course - the work was originally paid for by a travel company. And there’s a bit of a conflict of interest in a travel company getting people to think about booking a holiday by pointing out how miserable life is at the moment. But that doesn’t stop news outlets regurgitating the same old gibberish year on year and presenting it as scientific fact. It also hasn’t stopped other companies trying to capitalise on it, either.

And what better way to capitalise on it than to bring it forward! This year, drinks company Upbeat has announced that we’ve had it wrong all along. Blue Monday is a "myth", they claim – it’s not the third Monday of January we should be worried about. Instead, it’s the first week of January that’s the most ‘depressing’ for us. And to be more specific, it’s the first Monday back at work that’s the worst. So Blue Monday is a myth, except, er, that it’s not. Today’s the day when we should be feeling our most miserable.

Instead of relying on made-up equations, Upbeat has instead turned to the internet. Using a brand new tool called the "Upbeat barometer", it claims to have analysed millions of tweets over the past three Januarys, via some sort of sentiment analysis. In other words, by picking out negative phrases from tweets, you can assign each day in the month a score based on the number of happy or miserable tweets out there.

According to the press release, the results “…reveal a nation struggling to overcome a lack of sleep and bemoaning an inability to keep New Year's resolutions. Tweets relating to feeling guilty are nearly five times higher than average on the first Monday in January as people head back to work and realise that all their good intentions have already been long forgotten.” It sounds pretty bad. But if you’re wondering how you might be able to combat the blues, don’t worry, Upbeat has you covered. Just grab one of their protein shakes, and you’ll be back on track.

To be objective about it, no actual scientific studies have ever backed up any claims about Blue Monday. Ben Goldacre looked at the evidence in 2011, and found that the research literature is somewhat variable when it comes to seasonal variation in depression. Some studies show peaks in admission for depression in Spring and Summer, others in Autumn, and others in Winter. One recent study, published in December 2013 in the Journal of Affective Disorders, suggests that there’s actually no seasonal variation in depression in the general population at all, and any studies that do suggest it might have just overestimated the prevalence.

So this latest incarnation is worrying for a number of reasons. While at first it comes across as a re-packaging of earlier guff about Blue Monday for the sake of promoting a product, on closer inspection it appears to be more insidious in nature. We’re all bored of nonsense pseudoscientific equations now. But analysing Twitter activity is new and different. Upbeat has changed the game, and the press release comes across in a way that suggests that somehow, there is a clear way to quantify how "depressing" a given day is. But it is based on an assumption that has never been tested – that tweets are an accurate reflection of the mental wellbeing of the entire population – so it's impossible to know how meaningful or informative the research actually is.

And because it sounds more believable than a stupid equation, it further promotes the trivialisation of depression. Moaning on Twitter about having to go back to work after the holidays is not depression. Likewise, there doesn’t appear to be a generalised set of factors that will cause widespread depression across the nation at exactly the same time. Depression doesn’t work like that, and to suggest that it’s something minor that everyone goes through from time to time belittles actual clinical depression and makes those who suffer from it acutely aware of how difficult it is to explain to people what they’re going through.

It is incredibly frustrating that I’m not the first person to have to point out that anything and everything surrounding Blue Monday is a monumental load of rubbish, and that it will probably come up again next year, and the year after. It’s a stupid gimmick that has the potential to undermine public confidence in science and the perception of scientists, and it downplays a serious mental health issue. All for the sake of selling a drink.