AT the age of 35, I am beginning to feel the effects of ageing.

They spring up on my face like the weeds in my garden - one day nothing is there; the next, a cheeky wee sucker is sprouting between the crevices of my sleep-deprived face. So when I arrive to meet Dr Darren McKeown, Glasgow's foremost Botox practitioner, I am sceptical - but intrigued. Recent years have left their mark on my face. As a working mother who has suffered many sleepless nights, my standard facial expression, even when happy, seems to be that of a frown.

"My passion in life is to help men and women feel better about themselves through the way they look," writes Dr McKeown on his website, adding that he aims "to give people the power to become the best version of themselves".

Should the way we look form the basis of our self-esteem? I suppose if McKeown were a psychologist, he would aim to make people feel better about themselves through the way they think and feel, so what's wrong with him using his expertise to do the same thing? Maybe nothing. But then there is that notion of helping people be the "best version of themselves". Is that always based on looks, and a younger version at that?

"It's not about trying to make people look younger," is McKeown's response when we meet. "If you need a filling in your teeth, you go to the dentist. If you develop a deep line or crease or you lose the fat pad in your face, it's about replacing that or filling that wrinkle in the same way you'd fill a tooth. It's about maintaining the face. For some people that doesn't matter - fantastic. But to the women that are bothered, it's about restoring rather than changing."

So it's not just about vanity? "With any other part of the anatomy that ages - heart, lungs, bones - you take medication to stop that ageing. I don't see the moral argument against it."

McKeown, 33, from Hamilton, fulfilled his "childhood ambition" to become a trained plastic surgeon and now specialises in non-surgical treatments like botox, fillers, laser skin rejuvenation, chemical peels and non-surgical eyelifts, among others. Full-on plastic surgery doesn't suit him, "because you're waiting for things to deteriorate to such an extent that you need dramatic surgical intervention". He sees his role as preventative. "You go to the dentist twice a year and he maintains your teeth. You come here twice a year and I look after your face."

We're at McKeown's Glasgow practice (he also has one on London's Harley Street). The styling is sleek: white leather settees and fragrant candles burning; McKeown didn't want it to feel clinical or intimidating. If you're going to get needles stuck in your face or your love handles frozen, using the latest in non-invasive fat removal, it should be in a homely, boutique environment, it seems.

Treatment room one is bright "and designed with really cruel lighting so every flaw shows up", explains McKeown. "The more I see the more that I can get rid of. So this is where most of the magic happens …"

Magic? Well, injectables - predominantly of botulinum toxin A, to give its full name, which works by relaxing, rather than paralysing, facial muscles. Without question, Botox has revolutionised the facial anti-ageing industry; the global Botox market is expected to reach around £1.8 billion by 2018. In Scotland, the industry has defied the recession and is growing every year in Glasgow. Clients, says McKeown, will change their shopping from Waitrose to Aldi in order to continue their Botox, and he agrees the practice of having cosmetic treatments is becoming normalised.

"People have started to realise you don't have to look like a freak if you've had cosmetic surgery. It is something that lots of normal women now do."

Does that make it right? Either way, he says, we're losing the social stigma associated with cosmetic treatments. So why do celebrities often look so awful and overdone?

"You'd be surprised," he replies. "I see celebrities going to particular practitioners and I think, 'Really? That's not who I would go to.' People get a reputation and it doesn't matter that the quality's not great."

The other issue, says McKeown, is that celebrities are constantly scrutinised for their appearance. They have a bad hair day and tomorrow it's in the press. The temptation can be to have a procedure to make themselves feel better. "Very often you see celebrities who have had a little bit of something and all of a sudden they've gone too far and it's all to do with how frequently they're topping up their procedures."

Botox and fillers last much longer than people think. "Top up" too frequently and, he says, "before you know it, you've got the overstuffed cheeks and lips".

It's not that people get "addicted" to treatments. Rather, he says: "They forget what they looked like before. After they had it the last time, they felt good, so let's have that done again. One of the most important things you can say in cosmetic practice is 'no'."

McKeown turned away the first five clients he had in this morning - unusual; normally it would only be one or two - but why? The first woman, he says, got "an amazing result" a fortnight ago so wanted more, "But there was nothing else to do." A second, he says, could benefit from treatment, "but it wasn't the right time for her. She was just out of an abusive relationship and someone in that frame of mind needs to deal with those other issues before having procedures".

For that reason, he says, it is important for him to know what's going on in his patients' lives. Many women, for example, decide to get their lips done when going through a divorce. "And I know that's not what they want; it's just a phase, they feel the need to change something and it's not the right thing to do."

Is McKeown a looks-obsessed practitioner with a conscience? It seems so. And, inevitably, he is seeing more and more young women come through his doors. "It's insane," he acknowledges. "You wouldn't believe the number. We had one girl who was 17 and the most concerning part was she's already been having Botox elsewhere. Someone told her, 'Get Botox now and you'll never age.' And it's completely and utterly wrong."

So he won't treat them. Instead he gives these young women some harsh truths (if needed) about their lifestyle: stop smoking, adopt a good skincare range and quit using the "demon sun beds", as he calls them. "They don't like hearing it," he smiles, "But I'm doing them a favour."

He sees more premature ageing in Glasgow than in London; and says that if women start Botox too soon, it ultimately makes them look older because it results in muscle atrophy. Procedures, he says, shouldn't be the first port of call.

"There's a perception you can have whatever lifestyle you want and turn to Botox later to undo the damage. It doesn't work like that. What I can achieve for your skin depends on the raw materials I've got to work with. If your skin quality is seven out of 10, I'll get you to a nine. If you've destroyed your skin with sun beds and cigarettes and your skin quality is three out of 10, I'll maybe get you up to five. Botox, fillers and lasers are not magic."

The message on his own new skincare range - launched this month and aimed at women aged 25-35 - is clear. Every bottle features the slogan: "STOP ... the wrinkles before they start." But can we actually do that?

"No. Everyone's going to get wrinkles," he acknowledges. "It's about delaying the onset of ageing."

McKeown agrees women are under more pressure to look good than our mothers were - in part due to our "media-driven society" - but he also believes women's attitudes towards life have changed. While his grandmother was happy to fulfill her designated role, his own mother at the same age is now "all about holidays in Vegas and Marbs". (She also works as the practice manager and frequently gets mistaken for his wife). Cosmetic procedures, he continues, "Give them [older women] an appearance on the outside that matches the way they feel on the inside."

Roughly 10-15% of his clientele are men. "Any kind of super-masculine profession - I will have seen them." The reason, he says, is David Beckham. "He has changed men's perceptions. It's now OK for men to want to look good."

But McKeown admits Botox and the like are not for everyone. "I would hate to live in a society where every woman felt they had to do cosmetic interventions. It is absolutely OK to age without it. The world would be wonderful if we were all completely satisfied with the way we looked, but for women who aren't, there are options, and it doesn't have to make you look unnatural."

Still, the industry gets a bad wrap. Is the media to blame? No, bad practitioners are, he says. McKeown often "fixes" other doctors' mistakes, and the women involved are frequently vulnerable. Some of the bad work he sees in London, he adds, is "bordering on criminal". Women who end up with "ducky lips" and "cheeks that are too big" give the profession a bad name.

"It drives me crazy," he says. "I had a lady with awful results recently and it was done by a podiatrist - doing Botox! Everybody's having a shot at it."

McKeown believes himself to be part of a "creative industry" - but one that needs tighter regulation. "If you turn up at a clinic above a sweaty salon in a dirty little room by someone with dubious qualifications or if you go round to your pal's house to get Botox injected in the kitchen ... People need to take more responsibility for researching their procedures. The reality is, there isn't the regulation in place and if you're not vigilant, you may end up looking like that woman in the picture," he says pointing to a recent client who had the stereotypical "bad Botox" look elsewhere.

I wonder if we would be better off in a world without Botox. What would he do to me? "Nothing," he answers. Really? "Not even this line?" I point between my brows. "You could possibly get a little Botox in to that but I wouldn't do much. You've got a youthful, plump face with a nice glow. Why would you want to do anything?"

McKeown's path to this point started with a childhood dream of becoming a plastic surgeon, after watching American TV and being fascinated by the beautiful women he saw on it. "My gran used to say, 'That's all that plastic surgery they've had'," he laughs.

He spent time in Los Angeles, just as Botox was becoming popular, and it changed his perception of the industry. Once he decided it was what he wanted to do, he wanted to be the best at it. Is that what motivates him?

"Yes. I absolutely love what I do. And over the years, I like to think I've developed an instinct for what's going to make a face look good. That's what I get from doing this all day, every day."

Darren McKeown's skincare range is out in Space NK stores nationwide and online ( from September 23. His clinic is at 202 West George Street, Glasgow;