Whey, pea or soy: Which protein powder is right for you

Whey, pea or soy: Which protein powder is right for you

Athletes, bodybuilders and gym rats can get obsessive about their protein powders. In addition to cost, taste and texture, shoppers carefully scrutinize the ratio of fat to protein and the exact mix of amino acids present in each powder.

But eco-minded gym-goers might want to consider one more factor: the impact their protein powder has on the environment.

The good news is, almost any powder you pick is going to be eco-friendly compared to eating a steak or a grilled chicken breast, according to a 2019 study from researchers at Arizona State University. “If I was giving advice for meeting protein requirements, I would definitely agree that protein powders have lower environmental impacts than eating meat in general,” said Andrew Berardy, the lead author of the study.

That’s because the most popular kinds of protein powder — including whey, pea and soy protein — come from plants or are byproducts of food processing, which cuts down on their carbon emissions.

Berardy warns that sustainability data on protein powders is scarce, and the numbers in his paper aren’t absolute. The environmental impact of any particular protein will depend on the seller’s manufacturing process, supply chain, energy source and so on. “Lack of transparency and data from such companies means this is difficult if not impossible to calculate,” said Berardy.

Still, there are some questions you can ask to gauge how eco-friendly your protein is. First, consider where it’s coming from, according to Marcial Vargas-González, the science and innovation lead at the environmental sustainability consultancy Quantis. Different options can be more or less sustainable depending on their raw ingredients.

“Protein powders that are using co-products, by-products or waste from other industries will have a lower impact,” he said. “Whey, for the time being, is a good option.”

Whey powder

Whey is one of the most popular types of protein powder on the market — and it’s also one of the most sustainable, according to Vargas-González.

“It’s usually considered pretty low-impact because it’s a low-value byproduct of the dairy industry,” he said. “There’s not much you can do with it, so it makes sense to use it as a source for protein powder.”

To make cheese, companies separate milk into curds — which they eventually turn into cheese — and liquid whey. Decades ago, whey was considered waste and sometimes dumped into streams, polluting waterways. That’s now illegal in the United States.

Instead, companies have turned whey into a commodity. They evaporate liquid whey until all that’s left is a protein-rich powder, which can be refined into the whey protein powder that is now common on the shelves at grocery stores and health food stores.

Because whey is a byproduct from cheesemaking, most sustainability experts tend to assign nearly all the carbon emissions and environmental impact of raising dairy cows to milk and cheese, and very little of it to whey. “You tend to allocate emissions based on economic value, so co-products usually get a lower impact assigned to them than the main product,” said Vargas-González.

That means that, on paper, whey has a very small environmental cost. “Some people argue that you shouldn’t do that type of calculation, because [whey] is still contributing to help maintain the dairy industry or lower its costs,” said Vargas-González. “This is kind of a philosophical or political question.”

For now, the world’s hunger for cheese is much greater than its hunger for whey protein powder, which means whey is still just a cheese byproduct. But if demand for whey gets big enough, it could start to catch up to the demand for cheese — and potentially motivate dairy farmers to raise more cows to sell more whey.

If that happens, whey would take on more responsibility for the dairy industry’s emissions and environmental harm and potentially become less sustainable, according to Vargas-González.

Pea-based vs. soy protein powders

If you’re vegan or lactose-intolerant, whey might not be an option for you. But there are plenty of sustainable plant-based powders on the market.

If you don’t know where in the world your plant protein came from, Vargas-González generally recommends pea-based options over soy. Soy is a “high-risk commodity,” he said, because farming for the crop can contribute to deforestation in places such as the Brazilian Amazon, where farmers burn forest to clear acres for planting. Brazil is the biggest soybean producer in the world. The Amazon is one of the world’s biggest carbon sinks, but its ability to store carbon is dropping as the rainforest burns.

But if you know that the soy in your protein powder didn’t come from a country with high deforestation rates, Vargas-González said he wouldn’t worry much about it. “Where it’s coming from can be more important than the type of plant-based protein” you choose.

Crickets in a tray of moistened peat at a Gym-N-Eat Crickets facility in Ames, Iowa.

Insect-based protein powders

There are a small number of insect-based protein powders on the market. Usually, they’re made from crickets. Sometimes, they claim to be more sustainable than alternatives like whey or pea protein.

But it’s hard to evaluate these claims without knowing the specifics of the bugs’ diets, according to Vargas-González. Insects reared on waste products from food processing are likely to be a very sustainable source of protein.

“But I’ve also seen cases of insect powders being produced by feeding [the bugs] soy,” said Vargas-González. “At that point, you might as well just get rid of the middleman … and eat the soy yourself.”