Ask Emily! Almond, Soy, or Cow: Which milk is more sustainable?

 
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Q: One question I have is, what's the best choice of milks? Organic cow's milk? Rice, almond, soy milk? Should I buy it in the carton or in the tetra pak boxes that don't need refrigeration? I'd love your recommendation on choosing the best milk option as a consumer. Thanks!
 

Emily

San Rafael, California

 

A: Great name, Emily. I’m excited to explore this question with you because it’s something I’ve thought about a lot. I think there’s some confusion out there about plant-based alternatives and whether they are even much better for the environment than straight-up cow’s milk. (We’ll get into your packaging question a bit later.)

Back in 2014, Tom Philpott of Mother Jones wrote an article called, “Lay Off the Almond Milk, You Ignorant Hipsters,” (a title his editors chose, he admitted) in which he basically says almond milk is a waste of perfectly good almonds. But I have to disagree, and I’ve dug into the data a bit for some justification.  

From an environmental point of view, there are a lot of reasons to lay off the cow’s milk (some of which were pointed out by Philpott). And although organic cow’s milk will have some environmental benefits (organic animals are raised without unnecessary antibiotics, for example), the water and climate impacts probably won’t be much different from conventional milk. The dairy industry generates a massive amount of pollution in the form of manure and potent methane emissions. A fun fact about methane: it mostly comes from cow burps, not farts—a fact The New York Times routinely forgets, I believe, because they know it’s funnier to write about farts.  

The good news is almonds do not fart or burp, but they do have a bad rep from the amount of water they need from  drought-stricken California. Which contributes to the idea that because almonds require a lot of water to grow, almond milk must be pretty water-intensive. But per cup, almond milk is less water intensive than cow’s milk. Also, let’s not forget that a lot of California water is used to produce cow’s milk, given that it is the top dairy-producing state, much to Wisconsin’s chagrin.

  Emily is all about making charts. Water footprint data derived from research by  Mesfin Mekonnen and Arjen Ysbert Hoekstra .

Emily is all about making charts. Water footprint data derived from research by Mesfin Mekonnen and Arjen Ysbert Hoekstra.

 

As Tom Philpott pointed out in his Mother Jones article, there’s only about a handful of almonds in an entire carton of almond milk. So almond milk doesn’t have a lot of protein in it, which is a big part of the reason that it ends up being the less water-intensive than soy and cow’s milk. If you’re relying on milk as a source of protein, I’d recommend you look to soy milk instead: Soy and cow’s milk have eight grams of protein per cup; almond milk has only one gram of protein. Most Americans get more than enough protein in their diets—roughly double what they need, actually—which is the topic of an upcoming column (stay tuned)!

Not only do plant-based milks typically require less water, they also have a smaller carbon footprint. Per cup, soy and almond milk have about half the carbon footprint of gassy cow’s milk.

 

  Cow and soy milk emissions from research by  Martin Heller and colleagues . Almond milk emissions estimated from soy milk processing emissions and the  carbon intensity of almonds . 

Cow and soy milk emissions from research by Martin Heller and colleagues. Almond milk emissions estimated from soy milk processing emissions and the carbon intensity of almonds

 

And back to your question about the best packaging for milk, anything that can be recycled will be less of a climate burden than non-recyclables. Tetra Paks are lighter than glass, which means less fuel is needed to ship them from place to place. But because they are made up of a few different types of materials, some places can recycle them, and some don’t. Bummer.  

Tetra Pak claims their shelf-stable packaging prevents food waste, but I can’t find many resources to back that up. Their aseptic containers don’t need refrigeration during shipping, which could reduce waste and energy use. If they do prevent a lot of environmentally-expensive milk from going to waste, that’s a big win in their favor.

The big picture is plant-based milks will almost always have less environmental impact than cow’s milk. Like all food we purchase, we should make sure not to waste it.

Thanks for writing in!

 

Emily Cassidy is Sustainability Science Manager at the California Academy of Sciences.  Ask Emily any climate or sustainability questions by emailing AskEmily@planetvision.com!