Which Plant-Based Milk Should You Choose? New Research May Have the Answer

Plant-based milks continue to rise in popularity in the U.S., and each kind—almond, soy, oat, pea—offers unique benefits. But new research shows if you're concerned about your vitamin and mineral intake, some plant-based milks may be better than others.

In a new comprehensive nutrient analysis presented at the fall 2022 meeting of the American Chemical Society, researchers shared that two types of plant-based milk—pea milk and soy milk—had higher levels of four essential minerals found in cow's milk: magnesium, phosphorus, zinc, and selenium.

Specifically, pea milk contained the largest amounts of phosphorus, selenium, and zinc; while soy milk had the highest levels of magnesium.

"These plant-based milk alternatives could be important sources of these micronutrients if you're trying to reach the recommended dietary allowances for them," the project's principal investigator Ben Redan, PhD, a research chemist at the U.S. Food and Drug Administration (FDA), said in a press release. "That's why these data points are important to get out to the public."

Here's what to know about the mineral content of plant-based milks—of which there was a lack of information—and what it means for your own dairy alternative choices.

Pea- and Soy-Based Drinks Have the Highest Levels of Essential Minerals

For the study, researchers from the Institute for Food Safety and Health—a consortium that includes the Illinois Institute of Technology, the FDA, and members of the food industry—sought to better understand the micronutrient profiles of plant-based milks.

Micronutrients—the vitamins and minerals humans need to get from foods—perform all sorts of crucial functions in the body, from supporting bone health to promoting a good night's rest to taming inflammation.

Traditionally, cows' milk has been a major source of multiple important micronutrients in the American diet—particularly phosphorus, selenium, magnesium, and zinc, which are all micronutrients the human body can't make, and thus has to get from food sources, the research said.

But with more consumers turning to dairy-free, plant-based drinks, there has been concern that these dairy alternatives may not supply the same levels of vitamins and minerals as cows' milk. "These products have been increasing in popularity, so it is important to have data on their nutritional composition," Redan told Health.

However, it was relatively unknown which micronutrients many plant-based milks actually contained—levels of phosphorus, selenium, magnesium, and zinc are not required on the Nutrition Facts label. That is, essentially, why researchers sought to build a more thorough nutrient profile of popular plant-based milks.

Using a technique called inductively coupled mass-spectrometry, Redan and his colleagues analyzed the contents of two to three brands of eight different types of plant-based milk—specifically looking at their percent daily values of phosphorus, selenium, magnesium, and zinc.

"The types analyzed were almond, cashew, coconut, hemp, oat, pea, rice, and soy-based beverages for a total of 85 samples," said Redan, who added that "our results are from samples available in the U.S."

As it turns out, not all plant-based beverages are created equal, nutrient-wise.

"In the products we analyzed, we found that there could be high variation in micronutrients across brands," said Redan. "In one brand of an almond-based beverage formulated with added zinc, for example, amounts of this mineral were about five times higher than the other two brands of almond-based beverages without added zinc."

Though Redan did not specify which brands came out on top for best nutrient profile, certain types of non-dairy milk were clearly the (plant-based) cream of the crop.

The option with the highest amounts of the micronutrients in question? Pea milk.

According to Redan, on average, an 8-ounce serving of milk made with peas contained 396 milligrams of phosphorus (32% of the Daily Value), 11 micrograms of selenium (20% DV), and 864 micrograms of zinc (7.9% DV).

The runner-up, with the most magnesium of all drinks studied (plus sizable amounts of phosphorus and zinc), was soy milk. "On average, soy-based milk alternatives contained 38.6 mg magnesium per 8 ounces—9.2% of the DV," Redan said. And at the other end of the spectrum, coconut milk contained some of the lowest levels of all the micronutrients analyzed.

Dairy Milk Still Reigns Supreme—For Those Who Can Digest It

In recent years, it's become trendy to vilify cow's milk for its high calorie count, saturated fat content, and status as a common allergen. But dairy milk is loaded with protein and (you guessed it) micronutrients.

Ultimately, if you can tolerate dairy, you may not need to replace it with a plant-based milk—even one that contains ample vitamins and minerals.

In fact, none of the plant-based milks in the newest research could top cow's milk for zinc levels. Dairy milk also had the same or more of phosphorus and selenium than all alternatives except pea milk, as well as higher amounts of magnesium than all but hemp and soy milk.

There's also milk's most famous micronutrient: calcium. Though many plant-based milks are fortified with this mineral, dairy is a natural source of it.

"Cow's milk provides easily absorbed calcium and provides about one-third of the RDA for calcium in one serving," Lisa Andrews, MEd, RD, founder of Sound Bites Nutrition told Health. "It's also less expensive than plant-based milk, with the exception of organic milk."

Which Plant-Based Milk Should You Choose?

If you do require a dairy alternative (or prefer its taste), the study's findings may be helpful for choosing the most nutritious option.

Though magnesium, phosphorus, selenium, and zinc may not be listed on every nutrition facts label, they're still important for good overall health. And certain health conditions or risk factors may make you want to focus even more closely on these nutrients so abundant in pea and soy milk.

"The need for magnesium increases as we age and is also needed in higher quantities during pregnancy," said Andrews. "Magnesium may aid in laxation for constipation and in the prevention and treatment of hypertension."

As for phosphorus, it strengthens bones and teeth and may be especially helpful for people recovering from respiratory illness or eating disorders, Andrews said.

Selenium, meanwhile, is an antioxidant that might play a role in preventing cancer, cardiovascular disease, thyroid problems, and other diseases. And while it's rare to have a zinc deficiency, this mineral has gotten plenty of buzz recently for its potential ability to support ahealthy immune system.

Choosing pea or soy milk might come with other benefits, too.

"In addition to higher levels of phosphorus, zinc, and selenium, pea milk is less likely to be an allergen than other plant-based milks such as almond or soy," said Andrews. "Plant-based pea milk provides more protein per serving than almond, rice, or coconut milk. Unsweetened pea milk is also lower in sugar, making it a good option for individuals with diabetes or those following a lower-carb diet."

Not to be outdone, soy milk features benefits of its own. "Advantages of soy milk include lower cost and comparable protein, calcium, vitamins A and D, and B vitamins to cow's milk."

On the other hand, if pea or soy milk aren't your favorite plant-based drinks, never fear. All eight types of dairy alternatives studied contained at least some amount of magnesium, phosphorus, and zinc (though several, including almond, cashew, coconut, rice, and soy, did not have detectable levels of selenium).

It's also important to note that, while these four main micronutrients are important to health, each plant-based milk's nutrition profile is a bigger picture than its micronutrients alone.

Ultimately, depending on your health goals, any type of dairy-free milk alternative might be best for you.