Meat production is hard on the planet.
According to one 2021 study, meat accounts for nearly 60% of all greenhouse gases from global food production. Not only do livestock produce methane, but raising animals requires an enormous amount of land and resources. Another recent report found that three-quarters of global agricultural land is used for livestock.
Accordingly, the potential environmental benefits of reducing our reliance on meat are promising. One 2022 study found that reducing global beef consumption by 20% could halve deforestation in the next 30 years.
At the same time, many consumers are concerned about getting enough protein in their diets, and animal products are an easy way to get it. We asked experts about eco-friendly ways to get enough protein, and to balance our health needs with what’s good for the planet.
Why is it important to get enough protein?
Protein is one of the six essential nutrients that the body needs to function properly. Along with fat and carbohydrates, it is one of three macronutrients, the nutrients our bodies use in the highest quantity.
Its main role is to help the body grow and repair itself, explains Dr Debbie Petitpain, RDN, a spokesperson for the Academy of Nutrition and Dietetics. When you digest protein, your body breaks it down into amino acids, then reassembles those amino acids into whatever the body needs.
“They can become hormones or neurotransmitters. They make up our muscles and our bones. They’re in every single cell throughout the body,” says Petitpain.
How much protein do people need?
The typical protein recommendation, says Petitpain, is 0.5 grams of protein per pound of body weight a day.
This is a recommendation for “your average healthy adult”, says Dr Jessica Titchenal, a doctor of clinical nutrition and certified nutrition specialist. An individual’s protein needs varies depending on age, activity levels, medical conditions and genetics.
“Even if I lined up 20 people of the same age, same gender, same lifestyle, same medical conditions, their protein needs would still potentially be different,” she says.
The US government’s dietary guidelines suggest an individual adult intake of 46 to 56 grams a day, depending on factors like age, sex and activity level, and the UK government recommends a similar individual adult intake of between 45 and 55.5 grams a day, depending on similar factors.
How can you tell if you’re getting enough protein?
Apart from keeping tabs on their intake, how can a person know if they’re getting an adequate amount of protein in their diet?
Overall, Petitpain says, getting enough protein is not a concern for most Americans. “Most people are over-consuming the recommended amounts of protein without even trying,” she says.
If one is concerned, Petitpain says one sign of inadequate protein is poor healing: for instance, if you get a cut and it takes a long time to heal, or “you’re getting sick often and you’re generally run down”. (Being tired a lot, though, is not necessarily a sign of protein deficiency. “That’s probably more about the quality of the diet you’re taking in versus just missing out on that individual nutrient.”)
Titchenal says that ideally individuals would work with certified nutritionists to make sure they are meeting their body’s needs.
What are good environmentally friendly sources of protein?
A 2021 Oxford study that looked at the environmental impact of 57,000 different foods in the UK found that fruits and vegetables have a significantly smaller impact on the planet than meats and cheeses. In this case, experts recommend protein-rich foods like beans, lentils and other legumes.
Tofu or any other soy-based product also makes for a great vegetarian protein option, Petitpain says. “Soy provides the body with all those essential amino acids in every bite,” she explains.
Some fake meat products, like vegan chicken or plant-based burgers, may contain a lot of protein, but they also tend to be highly processed. (We’ll get into lab-grown meat later.)
Petitpain says there is a “giant question mark” over the nutritional value of these products. “They still are high in sodium and high in saturated fats,” she says. She adds that they can be a useful “transition food” for those who are having a hard time adjusting to a more climate-friendly diet. “Sometimes it takes a while to find what you like.”
Even if you don’t want to totally eliminate meat from your diet, it might still be worth increasing your intake of plant-based protein sources. Although most Americans get adequate protein overall thanks to high meat intake, according to the US dietary guidelines, they tend to under-consume specific protein subgroups. For instance, half do not consume the recommended amounts of nuts, seeds and soy products.
What are sustainable sources of animal protein?
If you’re not ready to completely cut out meat just yet, experts say there are lots of ways to reduce your consumption, and to choose less harmful products.
Overall, red meat has a larger carbon footprint than poultry or fish, says Dr Nicole Tichenor Blackstone, assistant professor of agriculture, food, and environment at the Friedman School of Nutrition Science and Policy at Tufts University.
When it comes to carbon footprint, water use or land use, “red meat tends to be worse than a source of poultry, like chicken”, she says.
Nevertheless, she says, “there are absolutely environmental sustainability concerns and animal welfare concerns with large-scale poultry production”.
Blackstone says that eating less meat – specifically red meat, but animal protein in general – is what matters most when it comes to moving the needle on climate change. Another alternative is to buy higher-quality, lower-impact meat products.
“This isn’t achievable for everyone, but the more you can buy directly from producers, or participate in a community-supported agriculture program, something where there’s a lot of transparency and sustainability, the better,” she says.
Petitpain also points out that some of the meat industry’s carbon emissions are related to transport. “So find a source that is as local to you as possible,” she says. She recommends asking your grocery where they source their meat from, or checking for any local meat markets in your area.
Simply cutting back on meat consumption is helpful too. Blackstone notes that while Americans often see meat as the centerpiece of a meal, it might be healthier for consumers and the planet to see it as more of a condiment.
“If you’re going to do a dish that has beef as a centerpiece, you could do half beef, half beans,” she says. “We can think more creatively about how to use meat and plant-based proteins.”
Is lab-grown meat a good source of protein?
It’s still too early to say, both in terms of its impact on the planet and on consumers. The USDA has approved the sale of chicken made from animal cells, but the product is currently not available for purchase. (Lab-grown beef, pork, or any other animal product will have to go through their own regulatory processes.)
“There have been hundreds of analyses of the environmental impacts of different livestock, poultry and seafood systems,” says Blackstone. “There have been six about cell-cultivated meat.”
• This article was amended on 15 March 2024 to correct the US government’s dietary guidelines. An earlier version said the government suggested an individual adult intake between 5 and 7 ounces a day, which is equivalent to between 141 and 198 grams; the correct figure is between 46 and 56 grams.
