February 2022 Issue

Plant Milks: Grain-Based Varieties Take Center Stage
By Densie Webb, PhD, RD
Today’s Dietitian
Vol. 24, No. 2, P. 12

“Milk without the Moo” is one grain-based milk product’s catchy logo. The idea for all plant-based milks, of course, is to offer a milklike product without the “moo” part. These beverages, which are processed to look (and sometimes taste) much like cow’s milk, are taking up an increasing amount of space in the refrigerated dairy section of supermarkets.

According to Food Manufacturing magazine, plant-based milks now account for about 10% of the total milk market.1 An increasing portion of that 10% are grain-based milks. The increase in grain-based options and their growing popularity likely is due, in part, to the growing number of people adopting vegan or plant-based diets because of concerns related to health, animal welfare, and the environment.

While almond milk and soymilk top the plant-based milk charts in terms of sales—many coffee shops offer either or both—grain-based milks increasingly are demanding attention. Oat milk, which Food Navigator dubbed the “current category darling,” ranks second in popularity only to almond milk. Hemp- and barley-based milks are some of the most recent additions to the grain-based milk category. Millet and quinoa are grains being researched and processed to create grain-based milks, but, unlike oat, barley, and hemp milks, aren’t readily available in the United States. Oat milk is undoubtedly the easiest grain-based milk to find locally.

It’s worth noting that any plant milk, including grain-based milks, can be labeled as “milk” in the United States—despite the fact the FDA has a “standard of identity” for the term “milk.” To date, the FDA hasn’t decided whether to force companies that make plant milks to remove the word “milk” from labels since they don’t fall under its definition of milk. In some countries, including the European Union, plant-based milk can’t be sold or marketed as “milk.” The same goes for yogurt products made from plant milks; they can’t be sold or marketed as “yogurt.”

It’s important for dietitians to be aware of the differences in these grain-based milks and their growing popularity. Clients and patients likely will have questions.

Grain-Based Milk vs Cow’s Milk
It’s impossible to generalize about the differences between grain-based milks and cow’s milk because the products are as unique as the grains themselves. The one incontrovertible fact is that none of the grain-based milks is nutritionally equal to cow’s milk. Proponents of grain-based milks, and other plant-based milks, say they’re better than cow’s milk for personal health and the health of the planet. The grain-based milks listed in the table on page 14 are lower in saturated fat and most provide at least as much calcium, ounce for ounce, as cow’s milk due to fortification. While dietary recommendations advise limiting saturated fat intake for heart health, the role saturated fat plays in heart disease is a controversial topic.2

All grain-based milks are cholesterol- and trans fat–free and contain little, if any, saturated fat. However, Amy Reed, MS, RD, SCP, LD, a pediatric dietitian and spokesperson for the Academy of Nutrition and Dietetics, says, “When a grain is used to make a beverage, many times some of the nutrients may be lost. Most plant-based milks are not nutritionally equivalent to cow’s milk, but including them in a well-planned dietary pattern may still provide adequate nutrients.”

Most grain-based milks are fortified with calcium and vitamin D, along with several other vitamins and minerals found in cow’s milk. But the bioavailability of these fortified nutrients hasn’t been as well established as it has been for cow’s milk.3 Calcium fortification among grain-based milks ranges from 15% to 45% DV. Vitamin D fortification ranges from 0% to 25% DV, and vitamin B12 fortification ranges from 0% to 50% DV.

Lack of Ingredients and Consistency
Moreover, dairy proponents emphasize the lack of some nutrients and absence of natural components in grain-based milks, such as milk peptides, believed to be associated with lower blood pressure, and conjugated linoleic acid, shown to have anticarcinogenic, antiatherogenic, antidiabetic, and immunomodulatory effects. They also suggest that dairy offers cardiometabolic benefits.4

And while grain-based milks, along with other plant-based milks, often are considered more “natural” than cow’s milk, proponents of cow’s milk say plant-based milks are highly processed products and contain several additives, whereas the processing of cow’s milk is only pasteurization, homogenization, and fortification with vitamin D and sometimes vitamin A. Milk’s ingredient list contains only “milk and vitamin D3 (and vitamin A).”

It’s also important to note that ingredients of grain-based milks vary greatly among brands. Not all oat milks or barley milks, for example, are the same, even within the same brand, so it’s necessary for clients and patients to read labels carefully if they want to avoid certain ingredients or additives.

Benefits for the Lactose Intolerant and Allergic
For individuals who are lactose intolerant or have a milk protein allergy, any of the grain-based milks, if not complete nutrition replacements, can take the place of cow’s milk in coffee, cereal, hot chocolate, and baking.

Boon for the Environment
One of the purported benefits of switching to grain-based milk from cow’s milk is that it’s better for the environment. Oatly claims that switching from cow’s milk to oat milk saves 73% in carbon emissions—the company provides detailed information on how it calculated that figure on its website.5 A 2018 article published in the journal Science concluded that any plant-based milk has a smaller footprint than cow’s milk when it comes to water and land use, as well as carbon emissions.6

More Costly
However, one factor that’s true across the board for all plant- and grain-based milks is that they’re far more expensive than cow’s milk. Costs range from about $9 to $16 per gallon, though they’re packaged in irregular amounts requiring some calculations to determine the cost per gallon.

Grain-Based Milks In Stores
Here’s some additional information on some of the grain-based milks on the market.

Oat Milk. The market for oat milk is the fastest growing among the grain-based milks. The oat milk brand offerings seem to be growing exponentially on supermarket shelves. While there are several national and store brands, the leader, as of now, is Oatly oat milk. The company originated in Sweden and introduced Oatly to the United States in 2016.

Oat milk generally is free from dairy, soy, nuts, gluten, and GMOs. However, Oatly concedes that its oat milk is produced at facilities that process other products containing top allergens, though the company says the facilities it uses follow all guidelines for cleaning and testing protocols to prevent cross-contamination. In addition, it tests products post production to ensure no cross-contamination has occurred. What’s more, Oatly’s US products are certified gluten-free, making them safe for clients with celiac disease or nonceliac gluten sensitivity.7 To be certified gluten-free, a product must contain less than 20 ppm (parts per million) of gluten. That’s the lowest level that can be consistently detected in foods using valid scientific analytical tools, and it’s the level that’s consistent with those set by other countries and international bodies.8 Experts disagree on whether most people with celiac disease can tolerate foods with minute amounts of gluten.9 So, it’s important to note that even foods certified as “gluten-free” contain tiny amounts.

Finally, calories in oat milk vary from about 90 to 140 kcal per 8 oz, depending on whether it’s full-fat, low-fat, vanilla or chocolate flavored, or a special barista formula. Unlike cow’s milk, some oat milk brands provide fiber, and most have no added sugars. The sugar content results from an enzymatic process that breaks down the carbohydrates in the grain. One study found that oat milk has a medium glycemic index (GI), while coconut and rice milks have high GIs.10

Barley Milk. As of this writing, there’s only one barley milk available nationally in the United States—the Take Two brand listed in the accompanying table. But as demand grows for plant- and grain-based milks, milks made from barley are likely to become more common. The company claims its barley milk is environmentally friendly because it’s made from a brewery byproduct—known as “upcycled barley”—comprising what’s left after barley has been extracted for the fermentation process, all of which would normally go to waste.

Hemp Milk. Living Harvest’s Tempt Hemp Milk was developed because the founder of the company had severe gastrointestinal disorders and allergies and found that hemp seeds and their products helped. Milk made from the tiny hemp seeds is unique among the grain-based milks in that it’s an excellent source of omega-3s and omega-6 fatty acids. Hemp is gluten-free, so hemp milk is an option for clients and patients with celiac disease or nonceliac gluten sensitivity. As with other grain-based milks, hemp milk won’t separate in hot drinks, so it can be added to coffee and tea.

Click to enlarge

Grain-Based Milks of the Future

Millet Milk. While not yet available in the United States, it will appear on supermarket shelves in the near future. In the meantime, there are many recipes online for making millet milk at home.

Quinoa Milk. There was buzz in 2019 about Oatly working on a quinoa-based milk tagged Quiny, but the product isn’t available in the United States. As with millet milk, it may enter the market in the not-too-distant future.

“Since quinoa and millet milk, and even oat milk, would be new to the US, there doesn’t seem to be adequate research to discuss advantages and disadvantages,” Reed says.

Bottom Line
Grain-based milks vary greatly in terms of nutrition, ingredients, and taste. Only a handful of brands dominate the market, but Silk recently released a line of oat milks and a plant-based blend made with oat milk and coconut milk. Despite their individual differences, all plant milks, including grain-based milks, are highly processed foods that mimic the taste and texture of cow’s milk. Most are fortified with nutrients, such as calcium, vitamin D, and vitamin B12, so they provide some of the important nutrients found in cow’s milk. They’re generally excellent choices for vegans and vegetarians and individuals who are lactose intolerant or have a milk allergy. Plant milks that are certified gluten-free are good choices for clients and patients with celiac disease or nonceliac gluten sensitivity. However, RDs should advise clients to read labels carefully and look for certification seals.

— Densie Webb, PhD, RD, is a freelance writer, editor, and industry consultant based in Austin, Texas.


1. Hale M. Exploring the growth of plant-based milk. Food Manufacturing website. https://www.foodmanufacturing.com/consumer-trends/article/21723117/exploring-the-growth-of-plantbased-milk. Published September 23, 2021. Accessed December 3,2021.

2. Visioli F, Poli A. Fatty acids and cardiovascular risk. Evidence, lack of evidence, and diligence. Nutrients. 2020;12(12):3782.

3. Singhal S, Baker R, Baker S. A comparison of the nutritional value of cow’s milk and nondairy beverages. J Pediatr Gastroenterol Nutr. 2017;64(5):799-805.

4. Poppitt S. Cow’s milk and dairy consumption: is there now consensus for cardiometabolic health? Front Nutr. 2020;7:574725.

5. Oat drink with carbon dioxide equivalents. Oatly website. https://www.oatly.com/en-us/stuff-we-make/climate-footprint. Accessed December 3, 2021.

6. Poore J, Nemecek T. Reducing foods’ environmental impacts through producers and consumers. Science. 2018;360(6392):987-992.

7. Random answers. Oatly website. https://www.oatly.com/en-us/random-answers. Accessed December 3, 2021.

8. ‘Gluten-free’ means what it says. US Food and Drug Administration website. https://www.fda.gov/consumers/consumer-updates/gluten-free-means-what-it-says. Updated January 11, 2021. Accessed December 4, 2021.

9. Elli L, Bascuñán K, di Lernia L, et al. Safety of occasional ingestion of gluten in patients with celiac disease: a real-life study. BMC Medicine. 2020;18(1):42.

10. Fructuoso I, Romão B, Han H, et al. An overview on nutritional aspects of plant-based beverages used as substitutes for cow’s milk. Nutrients. 2021;13(8):2650.