Sooner or later, it happens to us all. You’re walking down the street, minding your own business, when someone catches your eye in a shop window. For a split second, you wonder who she could be, this vaguely familiar middle-aged woman with a sour expression and a weary gait. And then you realise: it’s you. Oh, the horror.

I have many techniques for evading this unwanted spectre. On shopping trips, I veer away from all reflective surfaces until I’ve had time to compose my special “mirror face” (shoulders back, eyebrows raised, chin down). At home, the looking glass in my front room is fashionably distressed for full blurring effect. For my make-up, I mostly use the rear-view mirror in my car, because its restricted size means it can only display one feature at a time (a great relief first thing in the morning).

The other day, however, I lowered my guard. I was fishing something out of the cupboard under the bathroom sink, and I chanced to glance at the mirror over the basin. My eye alighted not on my face, but on my cleavage. And there they were, unmistakable in the cold autumn sunlight: wrinkles.

Quite why I was so surprised, I don’t know. Still, it was a nasty shock. A few frown lines is one thing; a crinkly cleavage is quite another. You can have as many expert bra fittings as you like, but no amount of underwiring is going to conceal a less than youthful bosom.

It’s an especially pertinent problem at this time of year, too, since the so-called festive season requires that even the most party-phobic attempt some kind of evening attire.

In my experience, most party get-ups offer a choice between bare arms, high hemlines and low frontage. Since I have, in the words of my dear father, “arms like a Russian shot-putter and knees like a Welsh washerwoman”, I have little choice but to exercise the third option.

Clarins Beauty Flash Balm has been a great friend to me in the past, and so it was to Clarins that I turned first. For long-term care, its Bust Beauty Firming Lotion (from £32.50; clarins.com) is great, a rich, creamy hydrator with plant extracts to replenish skin on what they rather coyly refer to as the “bra area”. Even better, though, was the Bust Beauty Extra Lift Gel, £36.50, which instantly plumped and smoothed: perfect for a quick fix.

For a great all-rounder, though, you’d be hard pushed to beat Soap & Glory’s Make Yourself Youthful Face Serum (£12.78; boots.com). This keenly priced powerhouse of skin-rejuvenating ingredients (brought to us by the woman who launched Bliss spas and the Fitflop) is versatile enough to be used anywhere, from face to bust to hands. Personally, I’m going to try the lot – and replace that treacherous bathroom mirror with a cupboard to keep them all in.

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