This is scientific American 60 Second Science. I'm Julia Rosen. Got a minute?

You know those nutrition guidelines the government issues every few years?

It turns out that following them isn't just good for your health.

It's good for the planet, too.

What we found is that impacts vary across nations, but in high impact nations in general,

you can see that if you follow a nationally recommended diet

despite the fact that these diets don't mention explicitly or most of them don't

explicitly mention environmental impacts that you are going to have lower the environmental impacts

due to that.

So that's sort of fairly clear across all the high-income nations.

Paul Barron's, an environmental scientist at Leiden University in the Netherlands.

The food we eat takes a big toll on the environment. A third of the ice-free land on Earth is used for agriculture

and according to some estimates

producing food accounts for roughly a fifth of all human-caused greenhouse gas

emissions. Fertilizer runoff also leads to other problems like the algae blooms in Lake Erie and the

dead zone in the Gulf of Mexico. However, following dietary guidelines would

reduce those impacts, especially in wealthy countries like the US.

And most of the reductions come from meat and dairy,

which have an outsized impact on land use and pollution

and are a major source of greenhouse gases.

That's partly due to cow farts, seriously.

Heating recommendations would also mean eating fewer calories,

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