The year 2001 was more eventful than most and, a decade on, we're inundated with anniversaries. September was 9/11, this month the invasion of Afghanistan and next month the release of the first iPod. To which we could add the foot-and-mouth crisis, the Gujarat earthquake and the first ever entries on Wikipedia.

With so many significant events to look back on, one thing that few people will remember 2001 for is its entry in the UK's Material Flow Accounts, a set of dry and largely ignored data published annually by the Office for National Statistics.

But, according to environment writer Chris Goodall, those stats tell an important story. "What the figures suggest," Goodall says enthusiastically, "is that 2001 may turn out to be the year that the UK's consumption of 'stuff' – the total weight of everything we use, from food and fuel to flat-pack furniture – reached its peak and began to decline."

Quietly spoken but fiercely intelligent, Goodall is a consultant and author who, over the last decade or so, has established himself as a leading analyst on energy and climate issues. Probably the only Green Party parliamentary candidate who also used to work at McKinsey, his speciality is trawling through environment statistics that would send traditional eco-warriors to sleep.

"One thing that's remarkable is the sheer speed with which our resource use has crashed since the recession," Goodall continues. "In the space of a couple of years, we've dropped back to the second lowest level since we started keeping track in 1970. And although the figures aren't yet available for 2010 and 2011, it seems highly likely that we are now using fewer materials than at any time on record."

Goodall discovered the Material Flow Accounts while writing a research paper examining the UK's consumption of resources. The pattern he stumbled upon caught him by surprise: time and time again, Brits seemed to be consuming fewer resources and producing less waste. What really surprised him was that consumption appears to have started dropping in the first years of the new millennium, when the economy was still rapidly growing.

In 2001, Goodall says, the UK's consumption of paper and cardboard finally started to decline. This was followed, in 2002, by a fall in our use of primary energy: the raw heat and power generated by all fossil fuels and other energy sources. The following year, 2003, saw the start of a decline in the amount of household waste (including recycling) generated by each person in the country – a downward trend that before long could also be observed in the commercial and construction waste sectors.

In 2004, our purchases of new cars started to fall – as did our consumption of water. The next year, 2005, saw our household energy consumption starting to slump (notwithstanding an uptick last year due to the cold winter). And in 2006 we seem to have got bored with roads and railways, with a decline in the average distance travelled on private and public transport. All of this while GDP – and population – went up.

Other consumption categories have been falling for much longer, Goodall points out. Despite concerns about the increasing intensity and industrialisation of our farming, the amount of nitrogen, phosphate and potassium fertilisers being applied to British fields has been falling since the 1980s. Our consumption of cement reached a peak at a similar time.

Even our intake of food is falling. Although obesity is on the rise, the total number of calories consumed by Brits has been on a downward slope for around half a century, driven by the fact that, compared with previous generations, we do less exercise now and live in warmer homes. Perhaps more remarkably, our intake of meat – the food most regularly highlighted as an environmental concern – seems to have been falling since 2003.

Goodall's research sends a counterintuitive message. We might expect to have been getting through less stuff since the financial crash of 2008; but surely throughout the boom years of 1990s and noughties, our rate of material consumption was steadily climbing in step with GDP?

Not according to Goodall. But do his claims stack up? One obvious counter-argument is the fact that we have "outsourced" our resource-hungry industries to China and other developing countries. After all, various reports have already made it clear that while the UK's own use of oil, coal and gas is falling, our total carbon emissions, once you consider all Chinese factories producing our laptops, toys and clothes, continues to rise steadily.

Oddly, though, when it comes to overall resource use – everything from maize to metals – the same doesn't seem to apply. At least, not if we believe the official figures from the Office of National Statistics. Each year, statisticians there estimate the UK's Total Material Requirement, the grand total of all the goods we consume, plus all the materials used in the UK and overseas to produce those goods.

The numbers are head-spinningly huge. Once you add up minerals, fuels, crops, wood and animal products, the UK churns its way through roughly two billion tonnes of stuff each year. That's more than 30 tonnes for each man, woman and child in the country – a giant stack of raw materials as heavy as four double-decker buses. (Or, more specifically, as heavy as four old- fashioned Routemaster buses. In an exception to Goodall's theory, some of the newer, more efficient buses are almost twice as heavy as the old ones.)

Although that's still a massive – and doubtless unsustainable – rate of consumption, Goodall's point is that our appetite for materials may finally be on a downward curve. In particular, he's excited by the fact that over the past couple of decades, we've significantly grown the economy without noticeably increasing our resource use. To use the jargon, Goodall believes that Britain has finally "decoupled" economic growth and material consumption.

If correct, this means we've achieved something that many green commentators believed was impossible. In his influential 2009 book, Prosperity Without Growth, academic Tim Jackson argued that while economies could become more efficient in their use of resources, genuine decoupling – resource use falling while GDP rises – remained a "myth". This view, and the argument that we therefore should aim for zero-growth economics, has become widely accepted in environment circles.

Goodall believes that the data from the Office of National Statistics, combined with his own research, challenges this assumption. "In 2007, just before the crash," Goodall says, "our total use of materials was almost the same as it was in 1989, despite the economy having tripled in size in the intervening years. And the peak in resource use appears to have been in 2001 – many years before the recession halted economic growth."

Jackson welcomed Goodall's research, describing it as "long overdue" and "exactly the kind of analysis that is sadly lacking at policy level and desperately needed as the basis for a green economy". But he also warned against drawing simple conclusions, pointing out that – thanks to Britain's investments in the global commodity markets – our economy was continuing to increase resource use even if we had started consuming fewer of those resources ourselves. "For those hoping desperately for stuff-free growth," Jackson added, "there is only cold comfort in these statistics."

Andrew Simms of the New Economics Foundation also doubts the significance of the UK reaching peak stuff. "Measures of our environmental impact are only meaningful when they're related to the planet's ability to keep up. For these findings to be significant, we'd need to be able to demonstrate that we're on the way to being able to live within our ecological means. And on that measure we're still a long way off target."

Jackson and Simms are certainly right that – even if the UK has started consuming fewer resources – it's hardly going to save the planet. Globally, resource extraction is rising, carbon emissions are climbing, rainforests are shrinking, oceans are acidifying and species are disappearing. Solving these problems will clearly take far more than stabilising resource use in mature economies like the UK.

Goodall acknowledges this. "I don't want to suggest for a moment that the world doesn't face massive environmental challenges. But the data I found does suggest the possibility – and it is only a possibility – that economic growth is not necessarily incompatible with addressing these challenges. If growth helps us get more efficient in our use of resources, and actually reduces our consumption of material things, then environmentalists may be very wrong to campaign for a zero-growth economy."

Bringing the debate back to earth, he adds: "It is a trivial example but economic growth, and the innovation that comes with it, have given us the Kindle, a way of allowing us to read books without the high-energy consumption required to make paper. Digital goods generally have lower environmental impact than physical equivalents and if growth speeds up the process of 'dematerialisation', it has positive – not negative – environmental effects."

The idea that the best way to get greener may be to get richer isn't a new one. Economist Simon Kuznets argued decades ago that only when countries get to a certain level of wealth do they start to reduce their environmental impact. In green circles, however, such thinking is controversial. While environmentalists accept that poor countries need to grow economically to lift themselves out of poverty, most are thoroughly sceptical that conventional growth-focused economics is compatible with saving the planet from impending disaster.

There is, however, an emerging pro-growth seam of environmental thinking. Earlier this year, writer Mark Lynas caused a stir with his book The God Species, in which he broke a trio of green taboos by calling for environmentalists to embrace GM foods, nuclear power and growth-based capitalism. GM food would allow us to leave more of the world as wilderness, Lynas wrote; nuclear energy would help us wean ourselves off coal; and climbing economic growth would give us the best chance of combatting global poverty and funding the technical revolution required to green our production of energy and goods.

Simms says that to call for economic growth as the solution to the planet's woes is to miss the point. "The important question is this: is your economy doing something useful, and doing it within environmental boundaries? If we want to create a happy, low-carbon world, there are better ways to do that than slavishly trying to enlarge our economies. Bear in mind that 50 years of GDP growth and increasing resource use in the UK has done nothing to increase our life satisfaction."

Ecological and economic arguments aside, Goodall's suggestion that the UK may have reached the point of maximum resource use throws up lots of interesting questions. Most fundamentally: is it definitely true? How can we be sure that consumption won't soar to new, even greater, highs when the global economy eventually picks up? And if we really have reached a peak, how did we get there? Was it just a matter of shifting to a more service-based economy? Can the internet – or even decades of green campaigning – claim the credit? Or could it be that our densely packed little island is running out of space for new buildings, vehicles and bulky goods? Could eBay and Freecycle be a factor, helping to keep more goods in circulation for longer? Or the fact that more of us are living in cities?

If we can understand how we levelled off British resource use, perhaps that information could help other countries do the same. After all, in a world that may soon be home to nine billion people, there can be fewer more important messages than – when it comes to "stuff" – less can be more.