London - Just call them super-Spanx. The latest shapewear from Playtex not only promises to cinch you in and smooth you out, but its makers claim it will zap your cellulite and make you drop a dress size, too.

Objective 1 Size Down pants contain mysterious-sounding “acti-mineral ceramic crystals”, which are woven into the fabric and apparently improve microcirculation by giving your thighs and bottom a continuous massage as you walk around. But do these new wonder pants work? Could I drop a dress size by wearing them every day for a month?

For a start, these are no ordinary knickers to look at or wear. They certainly make their presence felt. In fact, once I’ve managed to squeeze into the opaque skin-coloured pants - they go from yourwaist to mid-thigh, almost cutting off circulation - I feel like I’m wearing a girdle or other such instrument of under-garment torture.

Even if I could reach for the biscuit tin, I wouldn’t dare as I’m convinced flab will suddenly pop out of the top or bottom.

Plus, on day one, when I get undressed, my other half looks at me in genuine horror and gasps: “What the heck are you wearing?” This is going to be a tough month. I admit I have never craved a comfy M&S brief more.

Of course, it’s not the first time women have suffered for the sake of vanity. When it comes to cellulite, there are few lengths we’re not prepared to go to in order to combat the dreaded orange- peel effect.

Objective 1 Size Down pants cost £38 (about R450), which seems a small price to pay for dimple-free thighs and a svelte waist. But having to wear them for 28 days (this is how long the makers claim it takes to notice the effects) means quite a few pairs are required. Luckily, their mighty flab-holding power withstands the rigours of the washing machine.

So are they worth the pain? Well, after 28 days of constant use, I have shed a thrilling 2in off my waist and lost 5lb - without hitting the gym once.

I don’t care whether it was thanks to those magic crystals or the fact I didn’t dare look at a biscuit - either way it worked. So my other half will just have to get used to big pants. - Daily Mail