According to a survey carried out by a glossy magazine, Carrie Bradshaw had nothing on middle-aged British women. The average woman over 40 has 19 pairs of shoes (which seems quite modest to me), but 5% have more than 100 pairs (much more like it). A third of the women questioned felt terrible guilt about the shoes and admitted to lying to boyfriends and husbands about the purchases. This is despite the fact that they earned their own money, to spend as they wish.

That guilt, I think, is at the crux of women’s relationship with shoes, or indeed of their relationship with non-essential shopping generally: one part pleasure, one part guilt; one part pride, one part shame; one part exhilaration, one part remorse. After all, an addiction to shoe shopping — or to fashiony shopping of any kind — marks one out as shallow and overly concerned with the appearance of our extremities, when really we should be coming up with a master plan to eradicate world poverty, solve global conflict and find a cure for Aids. Women, eh? Such silly creatures.

However, it stands to reason that if I earn X and wake up one morning thinking I could do with some cherry-red patent-leather wedges (as I did only last week, funnily enough), then I am free to buy them forthwith. My wedges harm nobody, they fill my heart with gladness, and miraculously enough they don’t turn my brain to porridge: I can still function, still work, still find the time to worry about the Middle East.

So why the guilt? Why the shoving to the back of the wardrobe, the disingenuous “What, these old things?”, the swift dumping of the tell-tale receipt? Through years of intense self-training, I am now guiltless when it comes to shopping of any kind, and yet I understand other women’s widespread feelings of having somehow transgressed when they buy a new, and not strictly necessary, pair of heels. What saddens me about it is that the guilt isn’t about shoes, but about having the temerity to have fantasies, ambitions, dreams.

The bored, overweight, weary housewife who blows half a week’s earnings on shoes that she will never wear — marabou-trimmed mules, say, with skyscraper heels — isn’t so much buying footwear as allowing herself to dream of an alternative life, one in which she is a languorous beauty, rouged and perfumed, lounging about in a silk babydoll, waiting in her boudoir for something terribly exciting to happen.

This is far removed from any kind of childish “dressing up” — it’s about honouring a part of herself that she knows exists and that she won’t allow circumstances to kill off.

The mild, crushed-seeming woman who works in Accounts and wears bobbly cardigans, and who’s been saving for weeks to buy thigh boots that do up with ribbons doesn’t lead a secret life, but wishes she did. Her husband will be cross with her for buying “ridiculous” footwear that he knows she’ll keep in a box in the wardrobe, but that’s not the point.

The point is, she is being imaginative, acknowledging the possibility of otherness and being true to a part of herself that society (to say nothing of her husband and children) would probably howl with laughter at. I say good for her and good for her mental health. Let her buy all the shoes she wants — in fact, encourage her.

All shoes are about self-definition. Because they are democratic, unlike clothes — you’re rarely too fat or too poor for a really fabulous pair since fabulous shoes don’t have to cost the earth — they have become a fixation for some women, a kind of shorthand for What Might Have Been. (The rise and rise of designer handbags is about this too; ditto scent, the sale of which bankrolls the big fashion houses.)

Shoes, I would go as far as saying, are a form of therapy and an efficient one at that. They can say anything you want them to say, in public — “I may be wearing a suit, but I’m a minx really”, “I am capable and efficient”, “I am playful”, “I can run fast” — whatever. Or they can whisper to you in private and make you feel the world is full of possibilities. No wonder we’re addicted to them.

The idea of fashion as therapy has been embraced fully and quite boldly by Trinny and Susannah since their not entirely successful departure from the BBC. Their new ITV show, Trinny and Susannah Undress, has suffered from comparisons with their former programme, What Not to Wear, because the new format concerns not only fashion but also, in equal measure, relationships — tired, faltering ones that need rejuvenation.

It’s a clever idea, because it cuts to the chase of what clothes and fashion are all about — self-esteem, the face you choose to present to the world, ambition, fantasy, imagination, desire and so on. It doesn’t always work on screen, partly because T&S’s somewhat abrasive, gung-ho style can sit awkwardly with the delicate business of rekindling affections, but it’s a laudable attempt all the same.

The fact that viewing figures aren’t as stratospheric as expected is because we like our escapism to be escapist, not to remind us of our failings. A programme like Wife Swap works brilliantly because we’re — I hope — too busy thanking God that we’re not like the people on display to find parallels with our own lives. T&S Undress, in contrast, makes over people whose troubles are more or less universal, and may be uncomfortably close to home.

But it’s all good. I love reality television, T&S included, because it’s as valid a form of therapy as any other, whether you’re talking Alpha course, antidepressants, analysis, or going away for a holiday with your girlfriends to get away from it all. Anything that involves distance and reassessment — a kind of unhooking from everyday life and all its concerns — has got to be a positive and healthy thing.

Which brings us neatly back to shoes and their therapeutic role. Given that, I think we’re probably all agreed, we exist in a world that is obsessed with the exterior — obsessed to a, well, obsessive degree, because the interior may not be in terribly good nick. It would be easy to misread women’s love of shoes as yet another manifestation of a semi-delusional (“Angelina Jolie and I wear the same shoes!”), slightly desperate refusal to engage with the real world.

That would be wrong. They’re not a manifestation of denial, they’re a manifestation of hope. And who would begrudge us that?

india.knight@sunday-times.co.uk

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