IT’S always the small things that trip you up.

Nineteen days into a vegan diet, and feeling reasonably pleased with the way things had been going, I reach into the fridge and casually nibble some Edam cheese. Dairy produce, in other words. Damn. Vegans aren't supposed to eat dairy produce – no milk, no cheese, no eggs.

“Don’t worry,” Craig Tannock, a vegan of some 30 years' standing, and owner of several Glasgow vegan restaurants, says when I mention this to him later. “Vegan cheeses have been transformed in the last five years. Vegans don’t have to give up cheese any more. There are dairy-free cheeses that are completely acceptable."

I've been experimenting with veganism for a few weeks now, largely prompted by the fact that there's a two-day vegan event, VegFest, at the SECC (December 5-6), followed by Veganuary, which invites people to go vegan for January, 2016.

People become vegans for all sorts of reasons: for better health, for the environment, to prevent animal exploitation. The more I've read about the exploitation of animals, the more sickened I have felt. That was the main reason, for me.

For the past three years, I've been experimenting with veggie dishes. Quorn meat-free meals are great, as is Linda McCartney's own range.

But something was missing. I felt like a hypocrite: how can you be appalled by images of animal exploitation and still wear leather?

I'd been interested in PETA's work for a while: it's an outspoken, crusading sort of organisation, not afraid to stir controversy. Its website has much information about vegan lifestyles. My eye was caught the credo on the home page: "Animals are not ours to eat, wear, experiment on, use for entertainment or abuse in any other way." PETA's hard-hitting videos about animal exploitation are pretty hard to watch, which I suppose is the point.

But what is veganism? The comprehensive handbook, Becoming Vegan, stipulates a diet free of meat, poultry, fish, dairy products, eggs and gelatin. The vegan lifestyle excludes clothes made from fur, leather, wool or silk. Vegans don't use personal-care or cleaning products from animal-derived ingredients, either.

At home I try vegan recipes. Out goes full-fat milk: in comes soya milk and almond milk. Soy lattes become my new morning addiction.

Clothes, however, are a more complicated issue. From M&S, I buy non-leather shoes, an acrylic scarf and a belt made from cotton and elastodiene, which is a start, but hardly a full wardrobe. More work is needed.

"When I went vegetarian then vegan, I went for the full lifestyle," says Craig. "I haven’t worn wool or leather for decades. In terms of footwear, you just need to look at the labels and see what the various symbols mean and know what is and isn’t leather. Now, the rare times I upgrade my footwear, I’ll normally go to a specialist veggie or vegan outlet.

“Over time, you can pick up a lot of information. The great thing now is that there are so many other people around in terms of the internet. There’s much more a community, more resources, than there ever was."

"I really do feel that veganism is becoming more mainstream," says Jane Land, co-founder of Veganuary. "It's mentioned more in the news, and in Google Trends it has overtaken 'vegetarian' in the last few years as a search term. If you mention 'vegan' in restaurants, not only do they understand, but they have options on the menu. We'd like to think that Veganuary is maybe part of that, challenging people to try vegan for a month."

Yvonne Taylor, senior manager of corporate projects at PETA UK, believes veganism is becoming mainstream. In fact, she says, "it's actually hip and fashionable to be vegan. With all the reports about the environment and population growth, it all just comes together. More and more people are looking at it and thinking, 'I don't want to support this cruelty, this devastation of the environment, the treatment of people in Third World countries'. It's so easy to be vegan once you're into it and get used to it."

There's no doubt that veganism's image has improved in recent years. There are now around 300,000 vegans in the UK.

But can we get everything we need from a plant-based diet? "In terms of the main nutrients," says Dr Emilie Combet Aspray, a lecturer in human nutrition at Glasgow University, "assuming that you have a great knowledge of foods, the vegan diet should be able to provide you with everything you need, with the potential exception of vitamin B12. It depends on how strict a vegan you are – I know some vegans who take yeast product for the B12. Others regard yeast as an unacceptable part of the vegan diet. B12 is potentially a problem but it can be found in fortified breakfast cereals, for example. A B12 supplement might be a good idea.

Dr Combet Aspray says knowledge is the key, and that seems right.

I plan to continue with my vegan experiment. So far, it's been easier than I expected, though having been vegetarian for three years certainly helped, as there was no meat-eating habit to overcome. There are hundreds of vegan recipes available. Sourcing vegan-friendly clothes, however, will require more of an effort.

The thing is: it's worth it. Vegans avoid exploiting animals for any purpose and that's an impulse I feel more in tune with, notwithstanding the fact that I unthinkingly wore leather shoes for years. It's clear that I've got a lot to learn. But the first steps have gone well. The next ones hold no fear.

* www.vegfestscotland.co.uk; www.veganuary.com