CFE / MYTHBUSTER SERIES

Setting the record straight

Short, evidence-backed reads that take a widely repeated claim and check it against the actual research. New ones added regularly.

01

Are children bad for the planet? The maths says no

A once-viral statistic has scared a generation into smaller families. Here's what newer research actually shows.

LIVE →
02

Title of next mythbuster

One-line preview of what this piece will cover goes here.

COMING SOON
03

Title of next mythbuster

One-line preview of what this piece will cover goes here.

COMING SOON
CFE / MYTHBUSTER 06 MIN READ

Are children bad for the planet? The maths says no

A once-viral statistic has scared a generation into smaller families. Newer research tells a very different story.

IN SHORT

  • The claim that having a child is the worst thing you can do for the climate rests on outdated 2005 emissions data.
  • A 2023 paper using up-to-date trends found restoring replacement fertility would raise warming by just 0.05°C — by 2200.
  • Parents tend to have lower personal emissions than non-parents at the same income level.
  • A larger population can mean cheaper shared infrastructure and more people working on the problem.
the claim

"The single most important thing you can do to fight climate change is not have children." It's the kind of claim that's been repeated in geography classrooms, opinion columns and viral posts for almost a decade — often persuasively enough that people who want children decide against it.

1why it stuck

Surveys suggest a meaningful share of people cite environmental worry as a reason to have fewer children, or none. Even on a conservative reading — assuming only one in ten of those responses reflects a genuine, decisive reason rather than a convenient one — that's still roughly 1 in 100 people. In the UK alone, that could mean 700,000 people, over the course of their lives, choosing not to become parents because of a claim that doesn't hold up to scrutiny.

2what the evidence actually shows

  1. Old data, worse assumptions. The famous 2017 study behind the claim borrowed its numbers from 2009 research built on 2005 emissions data — close to the historical peak for per-person emissions in the developed world.
  2. Double-counting the future. That 2009 estimate also tacked on a "carbon legacy" for hypothetical grandchildren, projected using fertility and emissions trends that have already fallen sharply since.
  3. Emissions keep dropping. A 2023 paper is the first to build falling emissions trends into the model — and the answer changes completely: even a full return to replacement-level fertility raises long-run warming by only 0.05°C by 2200.
  4. Family life already lowers emissions. Moving in with a partner tends to cut personal emissions by roughly as much as going car-free, and a UK study found parents have lower personal emissions than non-parents once income is accounted for.

Restoring replacement-level fertility across Europe would raise long-run warming by around 0.05°C by 2200 — not 0.5, and not by 2100.

BOTTOM LINE

Nobody should feel obliged to have children. But nobody should talk themselves out of it believing it's an environmental sacrifice — the numbers simply don't support that trade-off.

Sources: Wynes & Nicholas (2017) · Murtaugh & Schlax (2009) · fertility/emissions working paper (2023) · UK household carbon study (2010) · Kuruc, population and environmental public goods (2026)