It's the beauty trend known for making A-listers look as if they've morphed into an other-worldly cyborg.

LED masks - devices that beam specific wavelengths of light on to the skin - are hailed by celebrities and beauty gurus alike for their apparent ability to reduce inflammation, fine lines and wrinkles.

Advocates say the light emitted stimulates skin cells to repair areas of damage and produces collagen - the protein that plumps the skin.

But now the same technology is being used to beautify the body.

Retailers are selling 'wraps' or belts fitted with thousands of tiny coloured lights to tone, tighten and even shrink the tummy. Others, like exercise recovery experts ThermoLab sell LED sleeping bags you can slot yourself into, while online beauty giant Cultbeauty is selling a light-up yoga mat for an eye-watering £1159.

According to skincare brand This Works, their £100 red light body wrap - which comes with a removable strap - can even shave 3cm off your waist, as well as reduce the appearance of stretch marks and crepey or sagging skin that's common after pregnancy. 

It's this product that caught my eye, as a beauty editor of two decades and mother left with unsightly sagging skin on my abdomen following my two pregnancies.

I'm already a big fan of LED technology. Small studies have shown that wearing a good quality mask combining both red light and near infra-red light several times a week can help boost collagen production, soften fine lines and wrinkles, improve pigmentation and reduce inflammation. 

I’m firmly committed to mine. While it involves some commitment and can take at least eight weeks to notice the complexion-smoothing results, skin really does become glowier and smoother. These days, I wouldn’t be without it.

As per the brand's instructions, the This Works wrap must be worn for 20 minutes three times a week. Within a month users see a significant change to their waistline, according to a trial conducted by the brand.

If it works, it's welcome news. A recent study linked a large waist circumference to an increased risk of a host of life-threatening diseases. Shrinking your waist could even be a more protective measure than losing body weight, the scientists from Johns Hopkins hospital in the US suggested.

But how does it work?

'Both red and near-infrared light is thought to activate the pores in fat cells, causing fat to leak into the surrounding tissue,’ says leading aesthetics doctor Dr Brendan Khong.

‘These are then processed and cleared through the body’s normal fat metabolism process.'

However he cautions: 'The fat cells shrink rather than get destroyed. So the claims about reducing waist size relate to the size of the fat cells, rather than actually changing the shape of the body.

'The trial the company ran only involved 20 people. There needs to be more robust clinical studies for me to be confident of a 3cm waist reduction.'

With a month to go before my holiday, it had to be worth trying to see if I could whittle away 3cm from my waist simply by wearing the belt and sitting on the sofa. 

First, I measured my waist - which turned out to be 71cm. According to Government guidance, a healthy waist circumference measures less than half your height - which is the case for me, thankfully.

I wore the belt, which is essentially a wide, flexible LED panel attached to an elasticated Velcro band, as per the recommended instructions for the recommended three times a week for 20 minutes, across four weeks. 

Putting the belt on was fairly straightforward, though, given it’s quite wide and covers most of the abdomen, I had to half lie down wearing it. Wearing it in the evenings to watch TV was the easiest way to incorporate it into my daily routine. 

It’s easy enough to use - you simply switch it on once it’s around your waist and it turns itself off again after 20 minutes.

So did it work?

After a month I grabbed my tape measure. My waist circumference to be 71cm – exactly as it had been four weeks earlier. So no, sadly, I didn’t get the all-important 3cm off.

But that doesn't mean I didn't benefit at all. To my surprise, I noticed a significant change to the skin on my middle throughout the month. 

It got gradually smoother, with far less crepiness. So, I’m going to carry on using it to help improve the skin tone and texture on my tummy. 

One thing’s for sure, when it comes to beauty tech, we’re going to be seeing more and more body-specific red light gadgets hitting the market. Dr Khong agrees: ‘We’ve already seen red light gadgets for skincare, biohacking and hair growth, so body contouring is a predictable expansion.'