I was enjoying a coffee with a friend last week when she suddenly stopped mid-conversation, whipped out her smartphone and took a picture of her skinny mocha with a hazelnut shot.

“Sorry,” she said, when I looked at her perplexed. “I’ve forgotten to do my happy days entry.”

If you haven’t come across this yet, 100 Happy Days is the latest viral trend taking hashtags by storm.

Those who take part are challenged to post a picture of something that makes them happy every single day until the 100 days are up.

“You should give it a try,” my friend told me. “It’s revolutionised the way I look at life.”

I snorted with laughter, sloshing my latte down my top in the process.

But later I logged on to the website behind the fad to find out more.

According to the creator of this forced fun, our “super-busy schedules” are stopping us enjoying happy moments throughout the day and, by making a concerted effort to try and be happy, we can all learn to recognise the “beauty” of our lives.

If you hadn’t already guessed from this vomit-inducing blurb, this chirpy challenge originated in the US.

But how has it managed to make such an impact in the UK? I always thought the Brits were a miserable bunch. Pessimistic, sarcastic, grumpy. We like it that way, don’t we?

Apparently not.

Because, in fact, a new study from the Office of National Statistics shows that, actually, Britons are getting happier.

Our happiness levels have risen in the last year alone ? with 77% of people over 16 in the UK rating their life satisfaction at seven or above, up from 75.9%.

In other words, more than three quarters of Britons are pleased with their lot.

I suppose I would say I’m one of them – which might be why I find the idea of posting a picture online every 24 hours to prove it rather odd.

The happiest moments of my day can’t really be captured in a still.

I’m happy when I hear a song I like; when I bury my face into my son’s neck and inhale the scent of his skin. I’m happy taking my dog out for a walk; at the feel of the sunshine on my skin. I am happy on the beach with the wind blowing my hair or when I hear the sound of my children giggling together in the bath.

None of these things can be captured in a photo, so I can’t help but wonder if the challenge will really do anything for me.

Perhaps it would be more beneficial for my husband – the most miserable man alive – to take part?

I suggested it.

“Come on,” I said. “Name one thing today that made you happy?”

“Getting to the end of it without dropping dead,” he replied, deadpan.

“Be serious.”

“Well,” he said finally, after baiting me with more ludicrous suggestions. “What makes other people happy?”

I took a look at my friend’s Facebook accounts.

It seems everyone is participating except me.

And what is more, some of my most cynical and intelligent pals appear to have become warm and fuzzy strangers, constantly on the lookout for stuff that may make them happy, camera-phone in hand.

One, who recently lost her job, is ecstatic about a slab of cherry cheesecake. Another, who is mid-divorce, is wildly delighted by the May sunshine. A third, who just discovered her boyfriend has been cheating on her, has snapped a pic of her new Manolo Blahniks.

Do the pictures ease the heartache then, I wonder?

In the case of the designer shoes I can concede they might.

Most of my friends on Instagram (a photo-sharing network) seem particularly cheered by a good meal.

“Bangers and mash for tea #100happydays,” trilled one.

“Check out my full English breakfast #100happydays,” bragged another.

While on Twitter the hashtag sees a new post almost every second from people around the world.

I watched the feed for a bit.

The pictures included a wonky cucumber, several smiling babies, a number of pouty selfies, some sunsets and a dog dressed in a bra and knickers.

Someone was extremely excited about a Zumba class; someone else was delighted with a French manicure. A third was pictured scoffing a dozen Krispy Kreme donuts.

But, I have to admit, in among the banal were a few people who really could spot the hidden treasures of everyday life.

There was a lovely shot of a toddler discovering her own shadow and one of a man breaking the seal on a new jar of coffee. There was a photo of a family splashing about in a swimming pool, one of an elderly couple arm in arm, a picture of hundreds of padlocks clamped to a wire fence, spelling out the word “love”.

Shots like these not only made these people happy – they left me smiling too.

And don’t get me wrong; I do get the principle of the experiment.

Having a reminder that every day holds happiness is a lovely idea and it’s rather nice to pause and reflect on something positive that has happened. To be honest I can’t see how tweeting a picture of blue sky, my lunch-time salad or my kids asleep will make me any happier than actually feeling the sun on my skin, enjoying the taste of my crispy croutons or taking that massive sigh of relief that my children are finally quiet.

But it would be wrong of me to pass judgment without first giving it a whirl.

That’s right ? #100happydays ? I am about to grin and bear it.

You can follow my attempt on my Twitter feed – @EllenWiddup.