Plant-Based Milk vs. Cow’s Milk: What’s the Difference?

Almond milk, soy milk, rice milk. The dairy aisle is changing. You’ve no doubt noticed a number of beverages offered as plant-based milk alternatives.

While traditional cow’s milk still dominates the market, research shows U.S. non-dairy milk sales are growing while cow’s milk sales have declined. One need only look at the refrigerator case at a grocery store to see that retailers are increasingly stocking more plant-based dairy alternatives.

Consumers shopping for healthy alternatives have a lot of questions. How do you get milk from a nut, bean or seed? Is almond milk healthy? Is soy milk dairy? What is the nutrient profile of plant-based dairy alternatives compared to cow’s milk? Are the plant-based alternatives really milk?

We posed these questions to a panel of nutrition experts: Dr. Ann Macrina, Penn State University, Dr. Dennis Savaiano, Purdue University, and Dr. Connie Weaver, Purdue University.

What we learned

Plant-based milks are made by grinding a bean or nut, then adding water, flavors, vitamins and minerals. The nutrients and amount of sugar in plant-based milk varies considerably based on how it was produced and what has been added. Cow’s milk contains protein, calcium, riboflavin and potassium. The nutrients are consistent in all products, but the amount of fat varies from no fat, low-fat and full-fat.  Calcium-fortified soy milk is the closest to cow’s milk, but it is lower in other nutrients than cow’s milk. Some plant-based milks are very low in protein, which can be a matter of concern for children and elderly. Plant-based milks are becoming more popular because some people prefer the taste and the variety of flavors. It is also preferred by people who are allergic or intolerant to milk. The experts urge milk drinkers to read the labels and make the choice based on nutrition, price and preferences.

From the experts

Read the in-depth interview to discover more about plant-based milk, nutrients and trends in the dairy aisle.

Why have sales of cow’s milk been declining?

Dr. Macrina: There are several reasons. Back in the day when most people were home for dinner in the evening, it was part of our routine for kids, and even adults, to drink milk. People today are on the go and often aren’t home for dinner. And, for a long time, milk wasn’t as portable as other beverages. Portable milk packaging has come a long way but I don’t think many people are fully aware of it.

Dr. Weaver: Also, some people avoid cow’s milk because of expected lactose intolerance or protein allergies, or dislike of the taste without making the effort to find products or strategies to incorporate them into their diet.

Dr. Savaiano: Over the last 30 years or so soft drink consumption has increased significantly and for some people, soft drinks have replaced milk as the drink of choice. This is concerning. If you look at the nutrient intake profile of Americans over the last 30 years, we are far away from recommendations. We don’t eat enough fruits or vegetables. We probably do get enough calcium. We’re on the edge of getting the right amount of riboflavin. The sodium/potassium ratios of what we eat are not great – less sodium and more potassium would be good.

Low-fat dairy can be a key component in an ideal diet. Soft drinks tend to contribute calories instead of nutrients and most Americans get more than enough calories.

Dr. Macrina: Some people think milk costs too much. If you can buy a two-liter bottle of soda for a $1.50, some will choose it over milk. People sometimes don’t think about the nutritional issue when they’re making purchasing decisions. If you ask a kid if they want milk or soda, which one do you think they’re going to choose? Also, kids used to drink a lot of milk at school, but schools have switched to very low-fat or no-fat milk which simply doesn’t taste that good to kids.

Market research shows plant-based milk substitutes are gaining popularity. Why?

Dr. Savaiano: It’s a very small part of the market, but yes, sales of plant-based beverages are increasing. It reflects that some people feel vegetable-based products are healthier. Some consumers also question modern milk production practices which also has had a negative impact on milk consumption. Depending on their composition, some of these plant-based drinks fall into the category of sweetened beverages. Some do, some don’t. It just depends on how much sugar is added.

Dr. Macrina: It’s interesting to note that while fluid milk consumption has decreased, overall dairy consumption has increased. People today are eating a lot of cheese and yogurt. But, some people perceive plant products as healthier than those from animals. Whether or not they actually are, some people believe they are allergic or intolerant to milk. A lot of the plant-based milks are flavored while there aren’t a lot of flavored cow’s milk products, other than chocolate, in many retail outlets. The plant-based products also tend to be sweeter, which is attractive to some.

How are plant-based milks made?

Dr. Macrina: Generally speaking, they grind a bean or nut then add water. The amount of water determines the consistency. Flavors, vitamins, minerals, etc. are added.

Dr. Savaiano: I’m not a food technologist, but if you look at the label you can see the ingredients. They contain components extracted from almonds, rice, soy, etc. The taste depends on what they’re flavored with and how they’re formulated.

Dr. Weaver: Soy milk, for example, is extracted from soybeans and if calcium fortified, a calcium salt is added. Similar for other plants.

What is the nutritional profile of regular milk vs almond milk and the other plant-based alternatives?

Dr. Savaiano: This is an important question because it can vary a lot. Consumers need to look at the label. Milk has lots of positive nutrients – protein, calcium, riboflavin, potassium. Milk’s nutrient profile isn’t perfect, but it’s a very nutritious food and, of course, it comes in no-fat, low-fat and full-fat varieties. The plant-based drinks can have a positive nutrient profile, too. It depends on the manufacturer.

Dr. Weaver: None of the plant-based options match cow’s milk entirely. Calcium-fortified soy milk is the closest to cow’s milk but still lower in potassium and some other nutrients. Some plant-based beverages are very low in protein as well (like almond milk) which can be a problem for kids and the elderly.

Dr. Macrina: The most variable component of cow’s milk is fat. The rest of it is relatively consistent – the protein and mineral content is going to be about the same regardless of the fat level in the milk you buy. Plant-based milks are quite variable. Some have as much fat as cow’s milk. Some have a higher sugar content. The big difference is protein. The quality of plant protein generally is not as high as animal protein. Cow’s milk has more of the building block proteins that humans need in their diet.

What’s your advice to consumers on milk replacements?

Dr. Macrina: Plant-based milks are quite variable in what they contain while cow’s milk is pretty standard. We know where cow’s milk comes from. Plant-based milks are manufactured and can have a variety of additives. I urge consumers to read the label to determine what’s best for them.

Dr. Savaiano: Yes, consumers should read the label very carefully. Plant-based drinks certainly can be a healthy choice depending on how they’re formulated.

Dr. Weaver: The plant-based beverages all cost a good deal more than cow’s milk. So, one needs to determine how much they want to pay for the nutrients and determine which nutrients you need to get from other foods. A main nutrient expected from milk is calcium. Only soy milk has been tested for calcium bioavailability (by my lab) which was determined to be as good as from cow’s milk. But none of the other plant beverages have been tested and they should be.

MilkPEP (Milk Processor Education Program) has created an interactive site comparing plant-based milk and cow’s milk  on factors such as calories and nutrients.

Some members of Congress have asked FDA to step in and determine whether plant-based drink products should be allowed to be called “milk.” Find out in the second part of this series Debate in the Dairy Aisle: Are Plant-Based Drinks “Milk”?