I was watching Professor Regan's pharmacy last night, having followed this series with some interest.

For those who don't know, Prof Regan is a scientist who takes issue with products that make scientific claims that they can't back up. Last night's programme threw up some interesting issues about ageing. 

Although Prof Regan didn't deny that fillers such as Restylane are very effective and do exactly what they say on the tin - fill in wrinkles - she also discovered that is is not necessarily your wrinkles that actually age you. 

She did this by going to a face recognition centre, where she was asked to guess the ages of numerous faces flashed up in front of her. They went past at high speed - in fact, said the scientist conducting the experiment, most of us can 'age' someone in around a tenth of a second (talk about first impressions....). 

Prof Regan guessed ages correctly within 2.8 years, and this is apparently typical. But what was interesting was that she could do this - as we all can - EVEN WHEN THE IMAGES WERE BLURRED. In the blurred pictures, wrinkles weren't visible so clearly, we must all of us judge age on more than wrinkles alone. 

He then showed her that there were two kinds of images - some had shown the full face, with hair and ears, while some had been close-cropped vignettes, showing only the centre part of the face, with no hair visible. With the vignette images, her accuracy rate had dropped to 3.8 years. 

Judging from this that hair might be more important than wrinkles in terms of guessing someone's age, Prof Regan then did another experiment. She took a variety of mothers and daughters and got them to swap hairstyles, with the help of some wig artists who duplicated the looks that the women were wearing. No other changes were made to clothes or makeup, and groups of subjects were then asked to guess the women's age.

Overall, the subjects put the daughters (now wearing their mothers' hairstyles) at three years older than their real age, and the mothers (now wearing their daughters' hairstyles) at four years younger than their real age.

The message of this is fairly simple - if you want to knock a few years off, get to a hairdresser, which is is a crumb of comfort for those of us who don't want, or can't afford, to go down the injectables route.  

The administration of Botox will now become a medical procedure, under new guidelines issued by the UK's General Medical Council.

The drug has only ever been available through doctors, but formerly it could be administered by anyone - including you or me - and the new guidelines are designed to tighten up this loophole.

Botox has come under much criticism in recent months for being too readily available at parties, or as a lunchtime procedure - even being injected into women who were drunk, and with no records kept of who had used it or where. Since it works by causing facial paralysis, it's good to see that its use will now be more closely monitored by the medical profession. 

Personally, I am against the use of Botox, but this is entirely on feminist grounds - I feel that men and women alike should embrace our facial expressions and be proud of the changes that occur in our faces and bodies as we age. I also dislike the idea of injecting a deadly toxin into my face.

However, there is very little evidence that Botox is actually harmful - it has been used by doctors for decades to freeze facial tics and twitches. 

I hear that Simon Cowell, the darling, doesn't know anyone who doesn't use Botox, according to the Daily Mail. Well maybe he should get out more. Its applications are clearly limited. Using Botox may be making him look younger, but it hasn't made him less of a shit, has it?