Amazing how the ideological U-turns come thick and fast after you hit 40. I’ve written in the past about the freakiness of Botox and procedures like it and about the evils of plastic surgery. It turns out that my opinions were shared by Alexandra Shulman, the editor of Vogue, who wrote last week about how she deplored any kind of procedure aimed at concealing the inescapable fact that none of us is getting younger.

“It would be depressing to give in to it,” Shulman wrote, adding that even the smallest, least invasive intervention is “crossing a psychological frontier into another country”, and thus the thin end of a fat wedge: one minute, you’re losing a few lines; the next, you have a face like a balloon stretched over a melon, with your eyes heading for the back of your head, like something that lives at the bottom of the sea.

I would have agreed with her until recently. Why is the public perception that lines and grey hair turn men into “silver foxes” and women into grizzled hags? Why do women not see the tragic neediness of wanting to look less like themselves and more like their teenage daughters? Why do surgery aficionados seem to find it hard to know when to stop and often end up pop-eyed and utterly smooth, like weird dolls with old bodies? And so on.

It’s not difficult to construct an argument in favour of growing old gracefully and thus against any kind of cosmetic procedure, surgical or otherwise (and, by extension, against hair dye and eyebrow tweezing). It’s rather trickier to come out praising such procedures but praise them I do, to the skies.

I noticed, just under a year ago, that my face in repose was looking grumpier and grumpier. Not wrinkly, which is good, but sort of frowny and fierce about the eyes. This is hardly surprising since I am quite grumpy, but that doesn’t mean I liked it. Short of smiling crazily from dawn to dusk, there seemed to be only one option. So I informed myself and eventually went off, with some trepidation, to a private hospital in London (cost: high; waiting list: six months).

Despite what anybody tells you, there are only three or four people in London who administer Botox properly and with skill, which is why there are so many people walking around looking frozen and/or mad. People on the waiting list include every beauty editor in town, as well as every other person you see on the telly and praise for their unadulterated “normal” girl-next-door looks, or admire for ageing gracefully. Ha!

As the doctor sat taking photographs of my grumpy face, I explained that I disapproved of Botox and was only on a sort of recce. Quite right, he said. Find out about it first, go away and have a think, maybe come back another time. However, this is what he would do – here, here and here – and this is the kind of result he would achieve and everybody would think I looked especially well and nobody would dream I’d had my face injected with botulism toxin.

Health risks, you say. Eating salami is apparently a health risk. Leaving the house is a health risk and so is staying in it, since we’re all being poisoned by our use of detergents. I’ll take the health risk that makes me feel better, thanks.

It took me, ooh, about 45 seconds to decide that I wanted the Botox and that I wanted it right now. He did his thing – lots of tiny pricks rather than two or three big ones is the idea – and afterwards I jumped out of bed every morning for a week to stare in the mirror and try to frown. The frown became slighter each day and after a week I’d stopped looking permanently cross. Result!

I could still wiggle my eyebrows, or raise them, or look furious – but only when I wanted to look furious. And, sure enough, lots of people since have told me how “well” I look. Not one had asked if I’d had “work” (I guess the cat’s out of the bag now). I showed some girlfriends who had screamed with horror when I’d first mentioned Botox and begged me not to do it and even they conceded that perhaps it wasn’t such a terrible idea.

I had another load of Botox a few weeks ago, with even better results. I was about to go to America to appear on The Today Show and mentioned to the doctor that I felt nervous about this. “I’m going to give you a present,” he said. “A tiny little bit of filler in the lines between your nose and mouth, about half what I’d normally put in.” I can’t tell you what a difference this made – although I’m grateful for the half-dose: too much filler is what makes certain actresses have extraordinarily smooth round cheeks, like hairless hamsters.

And I don’t think it’s the thin end of the wedge, either. Fans of cosmetic procedures used to divide into two camps: mad women, who ended up looking barely human and whose desire for “perfection” clearly hinted at some subsumed unhappiness; and rich middle-aged ones, usually socialites, who made a virtue of being “well preserved”.

There is now a third camp and as far as I can see it’s a new phenomenon: middle-aged women like me, who don’t fancy anything extreme and have no desire to compete with pert twentysomethings, but who nevertheless would rather not look like they’re about to knock someone out with a swift left hook or who don’t fancy brow cleavage – that stubborn line that lodges itself between the eyes – or who, while resisting the idea of being as smooth as a blancmange, aren’t really crazy about having jowls at the age of 38.

I don’t think feeling demoralised by jowls makes you insanely vain, or self-hating, or part of the conspiracy to make women feel ugly and inadequate: I just think it means you don’t like jowls. And why should you? They’re not nice.

To me, Botox (and, mmm, maybe fillers) now comes under the category of hair dye, tooth-whitening toothpaste and waxing. Sure, I could wander about looking like some kind of angry badger, with huge grey streaks, stained teeth and goatlike legs, but whom exactly would I be pleasing? What would I be achieving and who for? Would I be making any kind of point and, if it were valid, why would I feel so mirror-crackingly awful?

If I have indeed “crossed the psychological frontier into another country”, it’s one I recommend. I say, go for it. If you have horrible teeth, get them sorted. If you have dreadful skin, get it seen to. If you feel that you’re rather more prune than plum and it bothers you, go and see somebody about it. You have nothing to lose but your decrepitude and nothing to be embarrassed about whatsoever. Normal people have “work” done, too. And no, it doesn’t hurt.

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