Oat Milk vs. Milk

You have no doubt stood at the milk section of the grocery store, stared at all of the new, different types of non-dairy milk, and wondered what, if anything, it all means. Is there actually any difference between oat milk and whole dairy milk?

Oat milk is made from oat grains instead of the milk that comes from cows, making it wholly vegan. The two types of milk have different nutritional profiles. Whole dairy milk has more naturally occurring nutrients, while oat milk is often fortified with nutrients. Oat milk is less calorific than whole dairy milk.

In the rest of the article, we are going to look at:

  • Why you need to understand the difference between oat milk and whole milk 
  • Which is healthier
  • The difference in taste 
  • The pros and cons of each

Why Compare Oat Milk vs Milk?

You may be thinking that it is all just milk and that where it comes from does not make a difference, but that could not be further from the truth.

The meteoric growth of the non-dairy milk industry shows us just how much value there is in straying from the beaten path somewhat to discover what else may be available.

Even though the practice of drinking milk has been with human civilization for many thousands of years, the benefits of non-dairy milk have not been even a fraction as closely studied as those of dairy milk until very recently.

So while non-dairy milk may not have as much of a cultural presence, leaving a lot of people with limited knowledge of what they offer, there is a lot to explore on the topic.

This exploration can lead you to find out about types of diets you hadn’t even considered.

Whether oat milk is better than whole dairy milk or the other way around is not a question with a definite answer since this will vary based on each individual’s needs.

The importance of comparing the two milks is to determine which might be better for you personally.

1 Cup

Oat Milk

Whole Milk

















Whole dairy milk has a wider nutritional profile than oat milk.

This means that a lot more essential nutrients occur naturally in dairy milk than they do in oat milk.

Don’t worry, though. This does not mean that oat milk is devoid of nutrients.

Oat milk, like most plant milks, is fortified.

What this means is that additional nutrients, especially Vitamin A and Vitamin D, are added to it during the manufacturing process.

Because which of these nutrients are or aren’t added to the oat milk will vary by manufacturer, the best practice is to have a look at the nutritional label of the exact brand of it that you are buying to see what you will get with it.

What we can compare directly, however, is some of the elements that aren’t subject to fortification.

Here's a short video from Unbottled that explains more about what milk fortification is.

Next, we're going to look at how the two types of milk stack up in terms of their calorie counts, protein content, fat, carbohydrates, and calcium.


The calorie count in dairy milk will vary depending on how much of the cream is left in it.

To make the comparison easy and clear, the calories and all other figures will be compared between oat milk and whole dairy milk.

Whole dairy milk, with its cream not skimmed off, has the highest calorie counts of all of the dairy milks.

At 149 calories per cup, cow’s milk can substitute a meal if you drink enough of it. Whether you do this intentionally or not, drinking a high volume of dairy milk every day will add to your calorie intake significantly.

Oat milk, by contrast, is measured by the United States Department of Agriculture as containing only 120 calories per cup.

This is a reduction of about 20% for the same volume compared to whole dairy milk.


There is a significant difference between the two types of milk in terms of protein content.

Whole dairy milk contains 7.7 grams of protein per cup, which is about 15% of the recommended daily value for an adult.

Oat milk only has 3 grams of protein for the same volume.

This might sound a little strange since oats are generally regarded as having a decent protein content, with, for example, oatmeal cookies containing 5.8 grams of protein per 100 grams and oat flour containing a whopping 13.2 grams for the same mass.

This difference exists because cooking releases nutrients.

Although the protein content of oat milk is not bad, with whole dairy milk containing more than two and a half times the amount, it is useful to think about to what extent protein is important for your own dietary needs and adjust accordingly.


Whole dairy milk has just shy of 8 grams of fat per cup.

This fat is all from the cream, and the skimmed variants of dairy milk can have, if fully skimmed, absolutely no fat.

Oat milk has about 5 grams of fat, making it the lower fat option by a significant margin.

If cutting down on fats is a crucial part of your dietary plan, this is an important difference between the two types of milk to note.


Oat milk has a higher carbohydrate content at 16 grams per cup compared to just under 12 grams per cup for whole dairy milk.

Curiously, in spite of this, whole dairy milk has a higher sugar content.

While oat milk only has 7 grams of sugar, whole dairy milk has around 12 grams of it in the form of lactose, the sugar that gives milk its distinctive slightly sweet taste.

Predictably, because it contains no plant cells, whole dairy milk has no dietary fiber measurable within a cup of it.

Oat milk, by comparison, has 1.92 grams of dietary fiber in a cup, which is a whole 7% of the recommended daily intake.

bottle of milk on table with white background


Whole dairy milk has 276 milligrams of calcium in a single cup. This is not surprising since milk is famous for being a great source of calcium.

What might be surprising is that the cup of oat milk that was tested by the United States Department of Agriculture had a whole 350 milligrams of calcium, more than a quarter more than the dairy milk.

Calcium does not occur naturally in oat milk, but the manufacturers of it will fortify their products with a number of nutrients, calcium included.

Because the calcium in oat milk is fortified, remember to always check the nutrition label when buying the product to confirm how much has been added to that product since it will vary.


Whole dairy milk is known for that distinct lactose taste – slightly sweet, quite creamy, and with a texture a little bit more viscous than water.

Oat milk does not have any lactose, so perhaps it is surprising how similar to cow’s milk it tastes.

In spite of the lower sugar content, oat milk is often described as tasting sweeter than whole dairy milk.

It does leave a very different aftertaste compared to cow’s milk, justifying its oaty roots.

Adjacent to taste and occasionally confused with it is texture.

In spite of the obvious lack of cream, oat milk is manufactured in such a way as to offer quite a thick texture.

Although you couldn’t confuse oat milk with cow’s milk, it does get closer than one would think, making it a great substitute if, for example, you enjoy milk but would like to go vegan.

Oat Milk Pros & Cons

The nutritional profile of oat milk does not vary quite as wildly from whole dairy milk as a lot of the other plant milks do, and for this reason, the pros and cons are a lot more subtle.

Oat milk is not made from any animal products, so if you are a vegan, it becomes the obvious choice.

Similarly, if you are lactose intolerant and cannot drink cow’s milk as a result, oat milk becomes the easy winner of the two.

But let’s look at some of the smaller differences to help you make your decision.


Perhaps the most obvious benefit to drinking oat milk over whole dairy milk is the lower calorie count.

If you are trying to lose weight or just don’t want to add calories to your daily intake unnecessarily, drinking oat milk will allow you to consume a greater volume of the beverage guilt-free.

If you are worried about cholesterol, you're in luck! 

A study has found that the antioxidants in oats can be useful in working against the dreaded sterol.

The beta-glucan fiber in oats has the same effect, making oat milk an even more powerful weapon against high cholesterol.

And if none of that has won you over, the polyphenols in oats have been found to have both anti-inflammatory and anti-itching effects.

Oat allergies are very rare, certainly rarer than the allergies that prevent people from drinking a lot of other plant milks or lactose intolerance, which makes dairy milk inaccessible to those people.

Because of this, oat milk is one of the easiest milks to drink and available to a higher percentage of the population than most of the alternatives.


Protein is an important part of a healthy diet, and while oat milk does contain it, it does so at a much lower level than whole dairy milk.

You could, of course, simply drink more oat milk to make up this difference, but then you would be exceeding the calorie intake you would get from the same number of proteins if you were getting them from cow’s milk.

Oat milk is also higher in carbohydrates.

If you are on a low carb diet like keto, oat milk will be an even bigger violation of it than cow’s milk, which also contains carbohydrates, but less so.

two glasses of milk on cutting table

Dairy Milk Pros & Cons

The benefits and downsides to drinking whole dairy milk have been observed, studied, and shared across countless generations and are well known.

For that reason, the pros and cons we are going to look at below will be in the specific context of comparing it to oat milk.

Because of this, huge benefits like calcium will not be mentioned since oat milk is fortified to have it too.


Whole dairy milk is a lot higher in protein.

Protein has countless benefits, but one of the most common ones that it brings in modern life is diet-induced thermogenesis.

The short version is that your body needs to burn energy to extract energy from food.

Different foods need different levels of energy to burn. Protein needs more energy to burn than anything else, effectively moderating your calorie intake.

A lower proportion of the calories from whole dairy milk are from the carbohydrates, the balance being made up for by the fat and protein.

While this does not necessarily make it perfect for a ketogenic diet, it does make it a better option compared to oat milk, which is more carb-heavy, less proteinaceous, and less fatty.


Dairy milk is produced by cows.

Although the cows are not killed in the process as with beef, there is disagreement over to what extent dairy farming is cruel or justified, and for this reason, as an animal product, whole dairy milk is not vegan.

Ordinary milk also has a noticeably higher calorie count than oat milk, which means that it is a lot easier to enter a calorie surplus in any given day when you consume it regularly.

This may not be a problem for you, but if you are keeping an eye on your weight or looking to lose some, you may want to give whole dairy milk a miss.


We have learned today that the competition of oat milk vs milk is not a simple matter of which is objectively better.

By looking at the differences between them, hopefully you have gotten a good idea of which would better fit your own dietary needs.