David Attenborough on Population, Plastic and Meat: 2018 Interview

Originally published 2018-11-12.

In early October 2018, shortly before his BBC series Dynasties aired, Sir David Attenborough gave a wide-ranging interview to Evan Davis on BBC Newsnight. He was 92. His main message was that humanity's footprint has to shrink: people should cut plastic waste, eat less meat, and accept that global population growth cannot continue forever. He also said the US decision to leave the Paris Agreement would not stop a worldwide shift in attitudes.

Below is what he actually said on each topic, the context behind it, and how the facts have moved since.

Plastic bags: useful, but not the whole answer

Attenborough's 2017 series Blue Planet II is widely credited with turning ocean plastic into a mainstream concern, with scenes of seabirds and turtles harmed by waste. So it was natural that Davis asked about bans and charges on single-use bags, which many countries were introducing at the time.

His view was balanced. "We should do our best to avoid the use of plastic," he said, yet he warned against overstating what refusing a carrier bag achieves. In his framing, a bag charge matters mainly because it gives ordinary people a concrete way to act on their concern in a democracy. The bigger changes, he suggested, come from the choices of governments and industry, which is why electing politicians willing to act counts for more than any single shopping habit.

Meat and diet

On food, Attenborough said he was not a big meat eater but saw no biological reason to avoid it, since humans evolved as omnivores. His argument was about scale rather than morality. Feeding a growing world on meat-heavy diets means clearing forests and grasslands for grazing and feed crops, and he said the planet simply cannot absorb that. The practical conclusion, in his words as reported by IFLScience, was that we have to modify our diet.

That fits a broad body of research showing that livestock use a large share of the world's agricultural land while providing a much smaller share of its calories. Eating less meat, rather than none, is the change he was pointing to.

Why he says population growth has to end

The headline line came when the conversation turned to numbers. "In the long run, population growth has to come to an end," Attenborough said. He pointed out that part of the growth comes from people living much longer, himself included. His worry was that if we simply wait for growth to level off by itself, the total may already be too large for the planet to support sustainably.

The demographic picture helps put this in perspective. The UN's World Population Prospects 2024 projects that the world will grow from about 8.1 billion people in 2024 to a peak of roughly 10.3 billion in the mid-2080s, then decline slightly. The global fertility rate has roughly halved since the early 1950s, when it was about five children per woman. Growth continues for now mostly because of momentum: a large generation of young people is still entering the years when people start families, and life expectancy keeps rising.

In other words, growth is already slowing, as Attenborough expected. The open question is the one he raised: how large the peak will be, and how much land, water and energy those people will use.

Numbers versus consumption

Population is only one part of environmental pressure. How much each person consumes, and how energy and food are produced, matter just as much. A person in a wealthy country typically has a far larger carbon footprint than someone in a low-income country where families are larger. That is why many environmental researchers caution against treating population alone as the problem.

The approaches that reliably lower birth rates are also ones that improve lives: girls' education, access to healthcare and family planning, and economic security. Attenborough has long supported voluntary measures of this kind. A fair reading of his comments is a call to shrink humanity's total footprint, not to blame particular countries or families.

The Paris Agreement and the United States

In June 2017 President Donald Trump announced that the United States would leave the Paris Agreement. Asked about it, Attenborough said he was encouraged by a change in public mood around the world. "There's a groundswell internationally of recognizing what we are doing to the planet," he said, and he predicted the US position would come to look outdated.

The story since has gone back and forth. The first US withdrawal took effect on November 4, 2020. President Joe Biden rejoined, with the return formally completed on February 19, 2021. Trump then signed a new withdrawal order on January 20, 2025, which took effect on January 27, 2026.

Watch the interview

The clip was first broadcast by BBC Newsnight. The second video is a shared excerpt posted by the charity Population Matters.

What readers can take from it

• Small actions matter most as a signal. Cutting plastic is worthwhile, and it also shows support for wider policy change.
• Diet is one of the biggest personal levers. Eating less meat reduces pressure on forests and grasslands.
• Population and consumption go together. Education, healthcare and lower per-person footprints all help.
• Politics shapes the outcome. International agreements depend on who governs, which is why Attenborough stressed voting.

Sources: BBC Newsnight interview; IFLScience (October 5, 2018); Wikipedia: Projections of population growth (UN WPP 2024); Wikipedia: United States withdrawal from the Paris Agreement.