Public health campaigns and dietary guidelines urge us to eat less meat and include more legumes. But what does ‘less’ really mean? Researchers from DTU now offer a clear answer.
255 grams (9 ounces) per week. That’s the short answer to how much meat we can consume without endangering the planet—and it only applies to poultry and pork.
When it comes to beef, even modest consumption exceeds planetary boundaries. This conclusion comes from a scientific study published in Nature Food by researchers from the Technical University of Denmark (DTU).
So says Caroline H. Gebara, postdoc at DTU Sustain and lead author of the study.
“Our calculations show that even moderate amounts of red meat in one’s diet are incompatible with what the planet can regenerate of resources based on the environmental factors we looked at in the study. However, there are many other diets – including ones with meat – that are both healthy and sustainable,” she says.
How much is ‘less’?
The researchers’ first goal was to investigate whether it is even possible to fulfil the nutritional needs of the entire global population without exceeding planetary boundaries. According to the calculations, it is possible. But it will require a change in our food consumption on both a global and individual level, says Caroline H. Gebara.
“The global shift requires political action at the top level, while the individual shift will be much easier if we have better guidance and frameworks that support sustainable choices,” she says.
The next goal of the research was therefore to come up with concrete figures for how much of different foods you can eat without consuming more of the earth’s resources than it can regenerate, says Caroline H. Gebara.
“Most people now realise that we should eat less meat for both environmental and health reasons. But it’s hard to relate to how much ‘less’ is and whether it really makes a difference in the big picture. Therefore, based on the planetary boundaries, we have calculated a concrete figure – 255 grams of poultry or pork per week – which you can actually visualise and consider when you are standing in the supermarket,” she says.
In Danish supermarkets, a pack of two chicken breast fillets typically weighs 280 grams which is slightly over the limit of what one person can eat in a week without exceeding the planetary boundaries.
Not either-or
The research team’s calculations take into account a number of environmental factors such as CO2 emissions, the consumption of water and land use, as well as the health impact of a particular diet. In total, they have examined more than 100,000 variations of 11 types of diets and calculated their respective environmental and health effects.
And the calculations clearly show that a diet with even moderate amounts of red meat – beef or lamb, for example – exceeds planetary limits.
A pescetarian, vegetarian, or vegan diet, on the other hand, is likely to stay within the limits of what the planet can support. But this also depends largely on the specific products included in the diets.
In addition, different combinations of diets, such as vegetarian but with dairy or eggs, can also be sustainable.
And that’s exactly what Caroline H. Gebara hopes that the study will help more people realize: That a sustainable diet can take many different forms.
“For example, our calculations show that it’s possible to eat cheese if that is important to you, while at the same time having a healthy and climate-friendly diet. The same is true for eggs, fish, and white meat, but the premise is of course that the rest of your diet is then relatively healthy and sustainable. But it doesn’t have to be either-or.”
Reference: “Diets can be consistent with planetary limits and health targets at the individual level” by Caroline H. Gebara, Etienne Berthet, Madeleine I. D. Vandenabeele, Olivier Jolliet and Alexis Laurent, 21 March 2025, Nature Food.
DOI: 10.1038/s43016-025-01133-y
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8 Comments
Oh, sod off.
When all of the politicians, celebrities and people worth over then 300K a year switch over and never cheat then maybe think about it.
As usual we are ignoring the real issue. There are too many humans on this planet. Cut down on humans and change farming practices. Problem solved.
>> “Cut down on humans”
And what is your process to do such?
>> “And how would you change current practices? Are you a farmer or an agro-scientist?
“And what is your process to do such?”
Ask Netanyahu.
Or better yet, ask any radical Islamist…
The answer is obviously Soylent Green!
There’s no problem but a line of story someone made up. You like science? That’s the truth.
It’s a disease of humans, whisper something, and their mind cannot get free. ‘Snookered’ I think the term is.
Humans, even when rarely honest, are simply not smart enough to figure out what they’ll learn after doing – what is always a hair-brained venture. Cock sure you can eliminate Malaria by simply putting DDT in all the streams and ponds, you just go right ahead and do it. And every scientist in world stood around patting themselves on the back – they are SO SMART.
But when you go with that first idea that was half-baked and then no need to think further – you have the irresolvable state of humanity.