99% of people breathe polluted air
The World Health Organization estimates that 99% of people around the world sometimes breathe air that exceeds WHO pollution guidelines.
Where this was said
The Invisible Killer: Introducing Particulate Matter and Air Pollution
At 5:54 · chapter starts 2:40
With a series of imagined radio announcements — 'the level of particulate matter in the air today is above WHO guidelines' or 'the Supreme Court will delay oral arguments due to high particulate matter in D.C.' — Dubner makes his central thesis visceral: air quality should be as routine a data point as weather or traffic. He introduces particulate matter (PM2.5), tiny particles less than 2.5 micrometers in diameter, invisible to the naked eye, and emitted by everything from dust to fossil fuel combustion. Environmental economist Andrea Linos of Deakin University explains why economists are interested: if pollution impairs cognition and cognition drives productivity, then the true economic costs of dirty air may be far larger than anyone has measured. The stage is set for a detailed scientific investigation into pollution's effects on the human brain.
US concern about air pollution: 40%
In 1990, 58% of Americans said they had a great deal of concern about air pollution; today that number has fallen to only 40%.
Air Pollution Kills More Than Wars, Smoking, and Car Crashes Combined
Air pollution kills roughly 7 million people a year — more than double global COVID deaths in 2020, and more than 5 times annual car-crash fatalities. Economist Michael Greenstone says it's worse than cigarette smoking, wars, and auto accidents combined.
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Radiologists spend only 36% of time reading scans
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1 in 6 Americans on depression meds
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500 self-help techniques → 12 levers
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Cold exposure: weak long-term evidence
Cold exposure has good short-term alertness benefits but the evidence base for long-term health benefits is much weaker than popularly believed.
20 habit techniques tested; almost none worked
In a randomized study of 20 habit-formation techniques run on hundreds of people, almost none of the techniques produced statistically meaningful results.
Tiny habit users stick to the FULL habit more
People given a tiny-habit fallback option (e.g. 10 squats instead of gym) were actually MORE successful at completing the full habit, not less.
Habit reflection = standout technique
The most effective habit-formation technique was 'habit reflection' — recalling a past successful habit, writing down what helped, then applying those lessons to a new habit.
