I have been a vegan for seven years. I prefer chocolate cakes to lentils, I don't spend my evenings sifting through layers of moss in search of nutrients, I won't eat it just because you made it and I don't value sea kittens above humans. Although I had already been vegetarian for four years, I waited until I was about to leave home to tell my parents I was going vegan. Mum looked at me across the dinner table. "You're not going to be awkward about it though, are you?"

I went vegan for ethical, not dietary reasons. I do not think humans have the right to oppress or abuse other species simply because they are intellectually weaker. Toddlers are intellectually weak, but you're unlikely to find one in a casserole. To me, human rights and animal rights go together. Humans have a responsibility to care for animals and other humans because both have the ability to suffer. Both are capable of experiencing pleasure, fear and pain. I find discrimination on the grounds of species as distasteful as discrimination on the grounds of race or sex.

Ethical vegans are often asked variations of the same dilemmas. "If you were stranded in a barren wasteland, starving, and someone offered you a beef burger, would you refuse to eat it?" The answer is no. If I was literally starving and the hummus wells had run dry, I would eat the burger because my survival depended on it. But I don't live in a barren wasteland, I live in Manchester, and since Media City was built we've had shops here. It is unnecessary for me to consume animal products for nutritional purposes. Vegans can obtain all the nutrients available in an omnivorous diet with the exception of vitamin B12, which many vegan foods are fortified with.

In recent years, there has been a vast increase in the number of dietary vegans; the most high-profile being Bill Clinton and Mike Tyson. Some people go vegan as a way of losing weight or lowering their cholesterol, but they choose not to look into the ethics of their diets. They know how many calories are in a raisin, but they don't know that male dairy calves, useless to the dairy industry, are usually killed at birth. The same fate awaits newborn male chicks in egg farms and hens that cannot lay the unnaturally high number of eggs their industry demands. Many people are not aware that dairy cows are separated from their calves just days after they are born so humans can drink their milk. Free-range and organic farming methods are no exception. Animals, like humans, should not be viewed purely as economic commodities.

Another thing vegans are often questioned about is their priorities. "Why would you care about intensive cattle farming when there are children dying of malaria in Ethiopia?" There doesn't have to be a competitive element to compassion. We don't have to pick sides. "Sorry, I'm afraid I can only care about one thing at a time, and today's thing is sustainable recycling in Honduras. Now be a dear and pass me the stilton."

There is not a clear divide between ethical and dietary vegans, and dietary vegans have certainly increased the availability of vegan options. When I went vegan, most soya milk curdled in instant coffee, and the one commonly available brand of vegan "cheese" looked and tasted like plasticine. Vegan cupcakes are now impossible to avoid in the more self-consciously fashionable parts of town, and for this I thank the dietary vegans.

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