FASHION, IT APPEARS, IS GOING the way of food. Consumers are thinking not only about the clothes they like and can afford, but increasingly of how they are made and with what environmental consequences.

Writers such as Joanna Blythman publish engaging, often shocking, accounts of what goes on in food production. We know the story of the £2 chicken and the fate of the turkeys that end up as Twizzlers. But it has taken us longer to view cut-price clothes with similar suspicion. Green living guides hint at the horrors of mass-produced clothing, but it is still a business shrouded in mystery.

So I was hopeful about Sandy Black's Eco-Chic: The Fashion Paradox. Here was a chance to assess our insatiable appetite for cheap clothes, which has led to a booming textile production industry, employing more than 26 million people worldwide. She optimistically shows how the industry is changing, with both cutting-edge designers and high street shops trying to clean up fashion's dirty image. And the book asserts that - although fashion may be seen as inherently unethical because it is rooted in change and novelty - steps are being taken to make it more “green”.

This is not a light read, and Black makes it clear that ethical practice is riddled with complexity. I wanted to find out whether Fairtrade fabric is better than organic. Should I steer clear of anything made in China? And what about multinationals that claim to have cleaned up their act? But Black doesn't do easy answers. In the chapter on different fabrics we learn that polyester may be a non-renewable material, a by-product of the oil industry, but there is lower water consumption in producing cotton and, once made, the fabric can be recycled many times to a product of equal value.

Then there's the problem of disposal of our unwanted clothes. What is not sold by UK charity shops ends up in the hands of textile traders, who ship it to markets in the developing world. An Oxfam report in 2005 concluded that second-hand clothing imports are “likely to have played a role in undermining industrial textile production in West Africa”. Black tells us this, but then she points out that the second-hand clothes trade creates much-needed employment abroad, before leaving us with the fact that processing and distributing used clothes requires substantially less energy than making new ones.

Ethically, our clothes going to Africa may be dubious, but environmentally it is the right choice.

This is typical of the dilemmas that exist within the industry. Black lays out the facts and lets the reader make a judgment. The nearest thing to a solution is offered in the paragraph-long conclusion, in which she sums up by saying that “there is not one ‘right' answer to the seemingly insurmountable contradictions within fashion, but multiple solutions”. While Black's research is meticulous, she stops short of asking what all this means for the consumer. In the case of second-hand clothes, probably that it is better that we give our clothes to a charity shop than chuck them in the bin, but it would be better still if we cut down on how many we had in the first place.

But not buying is the unmentionable. It is easier to demonstrate how to buy differently than to suggest that it might be better to cut back altogether.

Black believes that design and aesthetics can steer us towards sustainable fashion, so long as everyone, from buyers to governments, gets involved. But I believe that there is something else we need to change, something that exists outside the fashion industry. Rather than looking to the rise of eco-designers to provide a guilt-free way of shopping, we need to change our own habits.

We must buy less. Ethical consumerism is something of a paradox. To be ethical, you need to consume less.

Eco-Chic: The Fashion Paradox by Sandy Black
Black Dog, £24.95; 256pp

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