Scientists, it appears, are starting to become aware of what yogis and spiritual seekers in India have known for centuries - that meditation has a positive effect on mental health. Now available on the NHS, a version called mindfulness-based cognitive therapy, combining a mixture of medication and meditation, is proving a popular alternative to solely prescription drugs as a technique for controlling depression, while several neuroscientists in the US have posited that meditation actually increases brain activity in the areas of the brain controlling emotion, happiness and enthusiasm. Despite the cautionary notes struck by these scientists as they warn that research is still in its early stages, the discovery has led to increased excitement for the potential of meditation to combat depression and mental illness, or even mundane unhappiness.

Having practised yoga for eight years, the last two as a yoga teacher, and incorporated meditation into my practice, this discovery does not surprise me in the slightest. People who engage in a sustained and consistent yoga practice that incorporates meditation are happier. They are less wracked by the urges to over-indulge in alcohol, cigarettes, crap food and drugs. Their minds are calmer, their tendencies to swing between extremes of emotion less pronounced.

However, very few people actually do sustained and consistent yoga practice, and if they do, the chances are meditation is omitted. Most people take a class once a week, do a few stretches, and skip the bit at the end where you have to sit still with your eyes closed for a few minutes. Yoga is considered by many merely as an exercise technique to improve flexibility and keep you toned, and meditation is that boring bit where you don't do anything.

As with most techniques imported from the east, both yoga and meditation have been watered down to suit a western sensibility in a manner that makes them almost unrecognisable from their origins. Yoga and meditation for dogs is offered alongside yoga for golfers, yoga for runners, anusara yoga, Sivananda yoga ... it's not enough to merely offer a technique for self-improvement in this day and age, we must "rebrand" that technique in order to make it as appealing and commercially viable as possible. Yoga centres in the west are often revolting places, full of lithe and toned tanned skinnies, supping wheatgrass, clad in organic stretch lycra and hemp cardigans.

Everyone smiles in an alligator-type way, as if they want to consume you on their spelt bread with ghee and then shit you out quickly before their digestive tract can absorb any calories. Yoga centres present themselves online in sleek websites claiming to offer a calm and relaxed home-from-home where stressed types can go to rejuvenate in a non-judgmental environment, and pay extra for rolfing, or colon cleansing, or hot stone therapy, or happy endings, techniques which will change your life and make everything so much easier - in just 40 minutes.

Meditation can change your life, but the kind of meditation the scientists are studying is a practise undertaken every single day for years, by, for example, Tibetan Buddhist monks, or hardcore yogis who are terrifyingly committed to mental and physical control. It's hard and it's tiresome and it's boring. It's not five minutes on an ergonomic cushion and then a break for carrot and beetroot juice, talking to the other flexible skinnies in their trendy outfits about that fabulous new vegan place which does amazing organic sake and is so exclusive.

In the yoga tradition, meditation must be undertaken alongside asanas - physical postures - that are practised six days a week, and it's considered such a powerful and dangerous tool that many traditions of yoga don't introduce meditation until the practitioner is extremely advanced. The point is that meditation, practised properly, can be life changing. However, what five minutes of deep breathing does is relax you. This kind of meditation is a placebo - a bit like basic yoga classes, when out of shape students lie on their mat snoozing happily while some inane teacher prattles on earnestly about how your presence in this class has really made a difference to the world, can you feel the love?

Do we really want to be happy in the west? It seems to me we just crave these constant eastern trendy fads westernised to our taste, dodging out of the real deal. We know exercise increases the production of endorphins, that pets can make us happy, that yoga decreases blood pressure and eases arthritis and a multitude of other things, we know that a sausage a day increases your risk of colon cancer by 20%, that alcohol leads to liver damage, and a high-carbohydrate diet is not solely responsible for western obesity, it's rather people's inability to stop eating - but we still screw up, and convince ourselves of the efficacy of that vitamin tablet or the nice organic stamp on our food packaging, as if it can cancel all the bad stuff out. We want it easy. We want health and fitness and happiness without putting in the hard work, having a bit of a laugh along the way.

I've seen hundreds of students take up their once-a-week yoga class and throw themselves enthusiastically into a vegan lifestyle, go all the way to India to seek their guru, and then ... well, as my British-born Indian friend says only half jokingly, "white people go to India to get laid". Meditation may go on to be proven scientifically as a wonder cure for depression, but whether you'll get anyone to sit down in silence for an hour a day with their eyes closed is another matter. The mindfulness-based cognitive therapists obviously don't think so, as what their programme incorporates is a westernised version of meditation, made palatable to our delicate sensitivities and only loosely linked to the kind of traditional meditation techniques taught in the east.

As a yoga teacher perpetually amazed by the levels of gullibility in my students - after one extremely basic class they uniformly proclaim they feel so much better (but all you did was stand up and breathe!). It sounds harsh to suggest that we're just too damn lazy in the west to do what's good for us, but perhaps it's true. Much of our yoga over here, our muppet techniques of meditation, are a colonised and commercialised placebo. It's great that many people will feel moderately happier merely because they feel like they're doing themselves some good, but it's sad they never realise the true benefits of the ancient techniques that have been lost in translation.