Is there anything more annoying than being told to cheer up when you're feeling down? Actually, there is one thing more annoying: this 'Keep Calm And Eat A Cupcake' tote bag, which is the most irritating thing ever created by a human. But 'cheer up' comes close, owing chiefly to its pointlessness: if you could cheer up by choice, you'd already have done so.

It's especially unhelpful when directed at the seriously depressed, which is why there's always so much outrage whenever the Daily Mail publishes another of those trollumns arguing that depressed people should just pull themselves together. (Which, in turn, of course, is why they run them in the first place.) It's also exceptionally obnoxious when used to harrass women in public places.

But a new Canadian study, published in the Journal of Personality and Social Psychology, lends weight to the idea that telling others to look on the bright side is unwelcome and counterproductive even when it's done with the best of intentions. The researchers, led by the psychologist Denise Marigold of the University of Waterloo, found no evidence that 'positive reframing' is helpful for people with low self-esteem – the very people, in other words, most likely to be targeted for the 'cheer up!' treatment.

On the contrary: in experiments involving imagined scenarios, questionnaires and roleplaying, these people revealed they didn't welcome positive reframing. Instead, they wanted 'negative validation' – comments encouraging them to feel that expressing negative emotions was appropriate. Those providing the support, meanwhile, were likewise better off when they abandoned the positive approach. Trying to boost people's moods left them feeling frustrated and worse about themselves, too.

The researchers explain their findings using the theory of 'self-verification', which holds that people try to maintain consistent views of themselves, even if those views aren't cheery ones:

When providers [of emotional support] offer negative validation, they convey an understanding and acceptance of the negative thoughts and feelings associated with the recipient's experience, leaving [low self-esteem individuals] with the sense that the provider is in touch with who they are.

This study cheered me up, anyway, since it's another piece of evidence to support a hobby horse of mine – namely, that 'positive thinking' backfires all the time, and that you should regard with deep suspicion anyone who promotes it. In this case, it's upbeat messages coming from other people that fail in their desired effect. But a 2009 study originating at the same university suggests that things are no less fraught when it's you telling yourself to cheer up. Self-help 'affirmations' like 'I am a loveable person!', those experiments demonstrated, made people with low self-esteem feel worse than if they'd simply not used them at all.

None of which ought to come as a huge surprise. After all, it takes a remarkably simplistic understanding of the mind to believe that you can simply issue it with commands – "feel better!" – and expect it to oblige. Instead, when you attempt to suppress certain thoughts or emotions, you risk putting them centre stage, because you're constantly on the lookout for them. Furthermore, we're prone to resist such instructions – from ourselves or from others – in order to preserve a sense of autonomy ("I don't have to do what you tell me!"). And when you instruct someone who's feeling bad to feel better, the not-so-hidden criticism is that he or she is behaving unacceptably, and needs to change: hardly a message that's likely to lift anyone's mood.

Telling someone to cheer up, in short, is exactly as aggravating and pointless as asking someone who's lost something 'Well, where did you last have it?' If the question were answerable, the item wouldn't be lost. And if 'cheer up!' worked, nobody would ever feel unhappy to begin with.