A new study documents the dramatic change in America's material diet from 1900 to 2020 – ongoing shifts in US commodity consumption patterns with profound environmental, economic, and geopolitical implications.
Published by Iddo K. Wernick of The Rockefeller University's Program for the Human Environment in the Elsevier journal Resources Policy, the paper details the consumption of 100 key commodities used to build cities, power cars, produce everyday products, and connect people. It charts transformative changes since the start of the 20th century in both absolute commodity demand (ABS) and demand compared to economic activity, called intensity of use (IOU).
And it concludes that, for much of the 20th Century, ABS for nearly all 100 materials grew steadily as did IOU for many of them. But the decoupling trend began around 1970 – coincidentally, the year in which Americans observed the first Earth Day.
Comparing ABS and IOU from 1970 to 2020, clear differences emerge: For many metals and minerals, the intensity of U.S. commodity use dropped. While some of this decline may owe to production shifting to other countries, the inclusion of 100 commodities demonstrates broader factors at play as well.
For 51 materials, consumption grew but more slowly than the economy, with per-person use of many basic materials staying about the same. For a small group of 8 materials, including three high-tech "vitamins" (rhenium, indium, gallium), consumption grew faster than the economy from 1970 to 2020.
By looking at a wide range of materials over time, the work creates a way to better understand whether industrial societies are using relatively fewer physical materials to support their economies.
And, while this study focuses on the United States, it points the way for all countries to understand the materials their economies rely on and what this means for the environment, economic strength, and security.
"For much of the 20th century, America's appetite for materials seemed insatiable," says Dr. Wernick. "From the steel that built skyscrapers to the petroleum fueling the automobile revolution, demand for key commodities outpaced economic growth."
Post-World War II industrial expansion saw aluminum, plastic, and other modern materials supplant traditional ones like iron and timber, enabling lighter, more efficient products, he notes.
"Constant change is here to stay, and the 1970s were pivotal, after many decades of unchecked growth in commodity demand. Slowdown accompanied maturation of infrastructure, growing environmental awareness and efficiency, and the shift from an economy based on extractive industries and manufacturing to one increasingly dominated by services.
America's changing appetite for commodities
The study divides commodities into three groups based on consumption trends between 1970 and 2020. In the first group, only 8 commodities saw demand rise faster than economic growth. In addition to the trio of metals important for superalloys already mentioned, this group includes the high-tech metal titanium, essential for aerospace and military applications. It also includes the high-tech protein, chicken, whose production soared thanks to efficiencies in poultry farming and dietary shifts.
The second group, 51 in all, consists of commodities that grew more slowly than the economy but still increased in absolute terms, such as petroleum and nitrogen fertilizers. These commodities offer an example of material use decoupled from economic growth, a phenomenon called "relative dematerialization," and may auger that the USA is passing peak oil, peak paper, and peak beef.
Then there are 41 commodities like iron ore, cadmium, and sodium sulfate whose demand declined in both absolute and relative terms. Some, like cadmium, mercury, arsenic, and asbestos fell out of favor due to environmental and health regulations, while others, like sodium sulfate, suffered from industry shifts such as the decline of glass container manufacturing. Astonishingly, the data show that the USA has passed peak water withdrawal.
"The decline in demand for some commodities underscores how technological and societal changes reshape material consumption," says Dr. Wernick. "Demand for iron ore, for example, once the backbone of the U.S. steel industry, plummeted as electric arc furnace technology made it easier to recycle scrap metal, reducing reliance on mined ore and metallurgical coal."
Similarly, the fall in sodium sulfate—used in detergents and glassmaking—illustrates the impact of shifts in consumer behavior and industrial priorities. Plastic bottles, for instance, largely displaced glass as the preferred beverage container, while energy-intensive production processes faced mounting pressure from rising costs and environmental regulations.
Data on the industrial consumption of lithium and rare earth elements in the United States show steady, surprising decline. As for several other commodities, Americans now consume the vast majority of their lithium and rare earth elements in imported products they consume, for instance as batteries or magnets. These commodities exemplify the offshoring of US heavy industry and the globalization of supply chains. In contrast, enormous US exports of agricultural products exemplify the opposite: the USA effectively exports cropland, water, and fertilizers and yet cropland and water are in Group 3 (ABS & IOU fell) and nitrogen and potash in Group 2 (ABS rose but IOU fell).
Dematerialization
Is America truly using relatively fewer materials? The study reveals a nuanced picture.
For many high-volume commodities like coal and iron ore, absolute demand has indeed fallen. For others, demand has decoupled from economic growth, growing more slowly than GDP.
Along with the shift of the American economy towards services, the decoupling suggests increasing efficiency in how materials are used. Advances in manufacturing, recycling, and technology have allowed us to do more with less. The study cautions against over-optimism, however, as the "Jevons paradox" looms large: increased efficiency can rebound through affordability and abundance in greater overall consumption, offsetting environmental gains.
The paper also emphasizes that the growing complexity of manufactured products raises the costs associated with isolating and recovering materials from used products. And, "Market success of renewable energy, electric vehicles, and batteries would redraw the global map of material demand," says Dr. Wernick.
The study points to American successes in reducing consumption, like the 55% drop in coal use between 2007 and 2021, driven by the switch to cleaner natural gas, as proof that large-scale change is possible. It also highlights the potential of increasing the share of nuclear energy to reduce material consumption in the US and even dematerialize hydrogen production, a favorite of futurists and technological purists alike. Increases in agricultural productivity through precision agriculture also promise future material reductions.
Says Dr. Wernick: "As the 21st century unfolds, the question isn't just how much material we consume but what we use and how wisely we use it."
"Technological leapfrogging is widely predicted but only time will tell whether developing nations will be able to avoid the USA's – and now China's – material-intensive growth pattern."
Concludes Jesse Ausubel, Director of the Programme for the Human Environment at The Rockefeller University: " Dematerialization has been a focus of our Programme's research for decades and the scope of this paper – 100 commodities, in many cases over 100 years – offers extraordinary insight into the past and future of what we like to call 'demandite' the stuff of modern life."
"Anyone ordering goods online knows that we need Ozempic not just for the human body but for the human economy. Wernick's paper shows the USA may finally be finding ways to become lean and why it's hard to stay that way."
