Good for? It's a skin-tightening procedure that lifts brows and upper cheeks, reduces large pores and tightens skin around the jawline and neck. Thermage says it works best on women aged between 35 and 60, when their skin isn't too lax. Unlike laser, it can be used on all skin types and colours.

What is it? ThermaCool uses radio frequency to heat the collagen in the middle and bottom layers of skin, which causes it to tighten immediately. We have three layers of skin, the top level or epidermis, the collagen-rich middle layer (dermis), and the subcutaneous layer, also known as the fat layer, which has a web of collagen fibres running through it. It's a “non-ablative” therapy, which means that it doesn't affect the top layer of skin - a cooling spray is administered during the treatment to protect it.

Ouch factor? An anaesthetic cream can be used to dull the pain, which is compared to hot needles. “I'll do it again in a few years when I've forgotten the pain,” one user says. But the discomfort is short-lived and is felt only for about a quarter of the time the treatment takes.

Clock-watching A session can take between 20 minutes and two hours, depending on which areas are focused on. One session is recommended for best results, which occur between four to six months after the treatment. This is because as well as having an immediate effect it also stimulates collagen growth.

The Wimpole Aesthetics Centre (www.wimpole aesthetics.co.uk ) says you won't need another session for 36 to 40 months.

Downtime None. But your skin may be red for a couple of days, and some people have swelling, blistering and bruising. The manufacturers say that you can go back to work straight after the procedure.

What to ask The manufacturers insist that the treatment takes place in a doctor's office and is carried out by someone trained by Thermage (www.thermage.co.uk ).

Cost Full face takes about 90 minutes and costs £3,500.

Dermatologist's verdict “Unlike many treatments this one really can produce effects, both beneficial and untoward, scarring and tissue loss at a deep level. It must be carried out under specialist medical supervision after proper assessment and with informed consent,” says Dr Neil Walker, consultant dermatologist at Churchill Hospital, Oxford.

Trick or treatment? It could be money well spent, but at £3,500 a pop, you have to really want to get rid of those jowls.

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