If I said I knew of a sure-fire way to lastingly improve your skin and that all you would have to do to experience this seeming miracle would be to sit for 13 minutes every week beneath a gently pulsing light with your eyes closed, what would be your response? Would you whip out your credit card and rush to book yourself an appointment? Or would you silently mark me down as yet another decadent, middle-aged, straw-clutching desperado who feels bad about her complexion?

To be clear, I don’t feel bad about my neck – not yet. But perhaps I am a middle-aged desperado all the same, for how else to explain my appearance at the Light Salon, a clinic that offers the very treatment I’ve just described? The child of scientists, I’m a natural sceptic when it comes to the claims of the multi-billion-pound beauty industry. I still wash my face, just as I’ve always done, with soap and water. I would no more spend a lot of money on moisturiser, Botox or anything else in that vein than I would run down the street in my underwear. Even if I didn’t have strongly feminist feelings about facelifts, I would still find them alarming both in theory and in practice. Yet here I am, hoping that I will shortly look a little rosier: a better version of myself, if not precisely a younger looking one.

It is all so easy, that’s the thing. This branch of the Light Salon is in Harvey Nichols in Knightsbridge. You can walk in off the street and because the procedure is non-invasive and has no side effects – no redness, no irritation – when you stroll out again you need not worry about terrifying everyone you encounter. I could turn up for a meeting and no one would be any the wiser. From start to finish, moreover, the whole thing takes only 20 minutes (the extra time is devoted to cleansing your skin before the treatment begins and moisturising it afterwards); I’ve waited in the queue at Caffè Nero for longer. Best of all, it is appealingly de-stressing: an enforced break in a busy day. Tiny goggles in place to protect your eyes, you’ve no choice but to close them and give in to the unseasonal warmth that will soon spread gently across your face. It’s like lying on the beach, save for the fact that you are fully dressed and, somewhere far in the background, you can hear the distant howl of a police siren.

Facebook Twitter Pinterest Shine on: a patient lies under LEDs as part of his photodynamic therapy for skin cancer. Photograph: Getty Images

What is the kit like? The Light Salon has various machines available, but in my case the aesthetician, Amy Fiddler, will set me up beneath the Healite, a unit developed by Dr Glen Calderhead, the man who is generally considered to be one of the godfathers of low-level light therapy (LLLT). The Healite uses light-emitting diode (LED) technology, delivered at a wavelength of 830nm, to promote cellular function. LEDs may be blue, red, or yellow. Blue lights are used to treat acne, killing the bacteria that are its cause and regulating excess oil. Red lights stimulate collagen and elastin, the two holy grails of anti-ageing. Yellow lights help with wound healing and rejuvenation, and temporarily increase blood circulation. This machine uses a combination of red and yellow lights, arranged on a unit some 15 to 20cm away from my face, and though the results are incremental – a full course of 13 treatments (yours for £350) is recommended to achieve lasting effects – I’m told that I am likely, nevertheless, to see an improvement in my skin in the next 24 hours. And so, I sit back and relax…

Its uses are not limited to skincare. It works for pain relief as well

On the line from Seoul, South Korea, Calderhead is telling me the story of the development of LED therapy and of how he first came to be involved with it. According to Calderhead, who trained in the UK as a pathologist and who maintains a healthy Scottish accent, phototherapy has two true godfathers. The first of these is Endre Mester, a Hungarian medic who, in the late 1960s, began experimenting with the effects of lasers on skin cancer. “He published a paper in which he revealed that he had successfully cured the leg ulcers of patients using a red light laser,” says Calderhead. The second is Professor Harry Whelan, a neurologist who, in the late 1980s, was working at Nasa’s medicine laboratory. Having developed a blue light to be used to activate chlorophyll on the space station’s hydroponic plant farms, he began to examine possible medical uses for the diodes. He then developed a red LED that operated at 633nm, and subsequently published a paper looking at its effect on pain attenuation and wound healing. Could Calderhead be described as a third godfather? “I’m not sure about that,” he says, laughing.

In 1976, Calderhead went to Japan to study on a six-month sabbatical and there he met Dr Toshio Ohshiro, an “outstanding” laser surgeon. “I was fascinated by his work to the extent that, after two weeks, he suggested I stay and study with him,” says Calderhead. “In the course of one laser treatment, to remove a birthmark on a woman’s sternum, he found he’d incidentally cured her post-herpetic neuralgia [a painful complication of shingles that affects the nerves]. Post-herpetic neuralgia lives in the intercostal muscles. We thought about this and we surmised that some of the light energy had penetrated beyond its target at a very, very low level – and this, of course, tied in with the findings of laser surgeons like Mester.” Ohshiro and Calderhead were duly encouraged to branch out, from laser surgery into laser therapy. “We played around with wavelengths and LEDs, and in 1988 we published the first book on LLLT.”

In 2002, Calderhead met the CEO of a company called Phototherapeutics, the manufacturer of an LED system named Omnilux. Soon afterwards, he became its clinical director. At this point, Omnilux was working on two heads: red and blue. Patients treated with red light for non-melanoma skin cancers on their faces reported that afterwards their skin was in much better condition generally. The blue had proved effective in treating acne, but only for a limited period. “My first job was to work out why eruptions happened again, and why the light also turned the skin darker,” he says. This led him to use both lights together (previously they had been used separately). He also changed the frequency of the wavelength from 415nm to 830nm. This new, combined head was effective for both healing and rejuvenation: 830nm was, he says, “the magic number”.

Facebook Twitter Pinterest Low light ‘godfather’: Dr Glen Calderhead

Calderhead now works at Lutronic, the Seoul-based manufacturer of the Healite. So how does LED therapy work? “LLLT is an exchange of photon energy. Each photon is a packet of pure energy without mass. The energy passes into the energy pool of the cell. If it has a job to do, it will do it better. The part of the dermis that makes collagen, for instance, will make better collagen faster. It produces a viable clinical effect with no damage.” Its uses are not limited to skincare. “In Australia, where clinics are taking it up, it has been found to be fantastic for burns.” Does Calderhead use it himself? “Yes. For pain relief. I have sciatic neuralgia in my left hip – an old rugby injury. I put myself under the Healite twice a week. If I miss this, I’m in agony.”

Some see it not as a backlash against Botox, but close to it

Calderhead believes the future for LED therapy is, well, extremely bright – though hospitals in the west remain reluctant to invest in it. “They have shied away because it is so associated with aesthetics,” he says. “But we can chip away at this reluctance, by making it easier to understand.” He believes LED therapy could, in the future, be deployed far more widely. “Anything that involves wound healing and pain attenuation. It will work on the muscular-skeletal system. It will work on nerve injury. Recently, it has been used in cerebral trauma, such as stroke. This is why I call one of my presentations ‘Join the Healing Revolution’.” What about side effects? Are there any? “No, no. People always ask. For 830, there are really none. For 633, you have to be careful what else is on the skin – for instance, perfume – because you can get a photosensitive reaction.”

In the beauty world, the popularity of LED therapy is growing exponentially. In part, this is due simply to its increasing availability. According to Louise Taylor, one of the founders of Dermalux, a Warrington-based manufacturer of LED systems, some 1,000 clinics in the UK now use her company’s devices. “There is a feeling in the market that LED is something you can have on an ongoing basis,” she says. “Unless you have issues of photosensitivity, there are no real limits as to how much of it you can have, and that’s one reason why it is expanding in clinics.” But it is also the result of word of mouth, particularly on social media.

When home-use LED light masks came on to the market they became an Instagram trend, Lena Dunham among those who posed wearing one (hers was by Neutrogena, and cost only £27.50; however, last July this product was withdrawn from sale in the US following “reports of visual effects” by users). More recently, Victoria Beckham and Alexa Chung have posted pictures of themselves wearing home-use masks (the effect is spooky: sort of Hannibal Lecter meets the Cybermen, with added colour).

Facebook Twitter Pinterest Facing facts: a group tries the Neutrogena mask, which was later withdrawn from sale. Photograph: Rex/Shutterstock

Some see it, too, as a cultural shift: not a backlash against Botox exactly, but something close to it. “I think there is that movement, yes,” says Dr Dennis Gross, the American dermatologist and skin-care guru whose home LED mask retails for £430. “I think people want prevention right now, and that is one positive benefit of LED. Botox doesn’t stimulate collagen. LED gets to the heart of that matter: you will have more collagen, and it stays there – it’s yours. It’s one of the most efficacious treatments in dermatology.” His patients love the fact that it requires no down time – no recovery period – and that if they own a mask, they can, as is not the case with Botox, have treatments at home. (Do the masks work? Calderhead says they will never be as good as a clinical-style system; the lights are too close to the skin to be fully efficient.)

Hannah Measures, one of the co-founders of the Light Salon – which will shortly launch a new LED “bib” to enable clients to treat their décolletage – agrees that clients are increasingly interested in a more gentle, more holistic approach to their skin. “There is a growing body of people who think: we can’t stop ourselves getting older and we don’t really mind wrinkles, but still, we want to be the best possible version of ourselves.” LED therapy, she says, connects to “wellbeing” as much as it does to anti-ageing. “Our new bib can be placed on the shoulder and, in trials, some patients have said it helps with pain relief,” she says. Hence her determination to keep prices at her business fairly affordable: “It’s so important to us that this is democratic.”

By now, you may be wondering how I got on in this brave new nurturing world (though a single treatment is hardly a fair test). Well, the experience is rather lovely. I hate the winter and the warmth on my face is delicious. I like having to sit still, too: an enforced period of calm. Afterwards, I do glow a little (though we might attribute this to several things). But alas, I will also develop a somewhat teenage-looking spot the next morning. Am I tempted to sign up for a full course? Yes, but only after my conversation with Calderhead, LED’s great evangelist. As he puts it: “We have proved that collagen and elastin are both improved by LLLT. But education is important. This won’t happen overnight.”