Science News - USA (2022-05-07)

2,000

1,500

1,000

500

0

26 SCIENCE NEWS | May 7, 2022 & May 21, 2022

B. LADYZHETS AND T. TIBBITTS

THE FUTURE OF FOOD | FOOD CHOICES

Going meatless one day a week brings down that figure to
about 1,600 kilograms of CO 2 equivalents per year, per person.
Going vegan — a diet without any meat, dairy or other animal
products — cuts it by 87 percent to under 300. Going even
two-thirds vegan offers a sizable drop to 740 kilograms of
CO 2 equivalents.
Kim’s modeling also offers a “low food chain” option, which
brings emissions down to about 300 kilograms of CO 2 equivalents
per year, per person. Eating low on the food chain combines a
mostly plant-based diet with animal products that come from more
climate-friendly sources that do not disturb ecological systems.
Examples include insects, smaller fish like sardines, and oysters
and other mollusks.
Tai agrees that not everybody needs to become a vegetarian
or vegan to save the planet, as meat can have important cultural
and nutritional value. If you want to “start from the biggest pol-
luter,” he says, focus on cutting beef consumption.
But enough people need to make these changes to “send a
signal back to the market” that consumers want more plant-
based options, Tubiello says. Policy makers at the federal, state
and local levels can also encourage climate-friendly farming
practices, reduce food waste in government operations and
take other actions to cut down the resources used in food
production, Waite says.

For example, the World Resources Institute, where Waite

works, is part of an initiative called the Cool Food Pledge, in

which companies, universities and city governments have signed

on to reduce the climate impacts of the food they serve. The

institutions agree to track the food they purchase every year

to ensure they are progressing toward their goals, Waite says.

Developed countries like the United States — which have been

heavy meat consumers for decades — can have a big impact by

changing food choices. Indeed, a paper published in Nature

Food in January shows that if the populations of 54 high-income

nations switched to a plant-focused diet, annual emissions from

these countries’ agricultural production could drop by more

than 60 percent. s

Explore more

s Monica Crippa et al. “Food systems are responsible for a

third of global anthropogenic GHG emissions.” Nature Food.

March 2021.

s Francesco Tubiello et al. “Greenhouse gas emissions from

food systems: building the evidence base.” Environmental

Research Letters. June 2021.

Betsy Ladyzhets is a freelance science, health and data

journalist based in Brooklyn, N.Y.

Per capita food system greenhouse gas emissions of various U.S. diets

Figures show estimated emissions related to food production for one year of each diet

Eating fewer animal products leads to a

major reduction in greenhouse gas emissions

tied to an individual U.S. resident’s diet.

SOURCE: B.F. KIM ET AL/GLOBAL ENVIRONMENTAL CHANGE 2020

Vegan

No

animal

products

Low food

chain

Plant-based,

but eats

insects and

mollusks

2/3 vegan

Eats vegan

2 out of 3

meals/day

No red meat

No beef, pork,

sheep or goat

Pescatarian

Eats fish but

no other meat

Lacto/ovo

vegetarian

No meat,

but eats

dairy

and eggs

No dairy

No milk or

other dairy

products

Low red

meat

No more than

450 grams of

cooked red

meat/week

One meatless

day

No meat

1 day/week

Typical

Average

U.S. diet

Kilograms of CO

2 equivalents