The latest fad to hit the Internet is yet another thinspiration one, straight out of China. Young girls are posting selfies of themselves measured against a piece of A4 paper. I tried it and as a size 8 to 10 I don't even make the cut. To be narrower than a piece of A4 you need to have an as waist you need to have a 20-25 inch waist or less. Virtually impossible for most human beings.
Whilst these trends come and go, this one is particularly worrying as it is absolutely focussed on weight.
Our society has never been so thin-obessed, with mannequins now an average size six and catwalks filled with undernourished models. I do workshops for young anorexic girls in a kids hospital - they all have the thigh gap, hip bridge and A4 waist, but their lives are in grave danger.
They are all bright and beautiful girls but through pressures of school, home and social networks they have resorted to self-punishment.
For it is a slippery slope in the losing weight game, skip a meal here and there, the pounds fall, until you feel slim enough and an eating disorder is established.
For there is no such thing as pretty enough, skinny enough, sexy enough. Even the stars of Hollywood such as Jennifer Aniston and Nicole Kidman lack confidence. It explains why women who have cosmetic surgery always want to do more. Perfection is an illusion, a fake Barbie mirage.
Psychologists have all proven that confidence comes from knowing yourself, and nurturing one's talents. Not from ones appearance. Infact spending time focussing on your looks - reading a magazine, surfing fashion on the Internet - actually reduces your self-esteeem.
Yet when you're doing something you love - riding a bike, solving a maths problem, playing netball, doing a presentation, writing a book, caring for a sick child...whatever it might be, that makes you feel good about yourself.
The A4 challenge is paper thin, and will leave young girls feeling despondent, depressed and disgruntled this week as super skinny photos whizz are around the web. How many of them will turn to diet pills, excessive sport, bulimia even?
As for the social networks they do little to ban or discourage such detrimental content. A friend asked me if her 11 year old child should go on Instagram. I was on the fence. Now I'm not. This is a tender age when insecurities can take root and stay with you for life. Ignorance is bliss in this case, tis folly to be wise.
For mothers, aunts, sisters, godmothers, don't sit back and watch young girls succumb to this trend, stand up for them, for what's right.
Every body is beautiful, not just the thin ones, because inner beauty is shines brighter than any hair, skin, or teeth.