Promo code SPRING2022 will be automatically applied at checkout!

Oat Milk and Blood Sugar: What You Need to Know

Christie Borders, MS, CNS

Published in Nutrition

8 min read

August 19, 2022
October 30, 2023
A bottle of oat milk
A bottle of oat milk

Oat milk has become one of the most popular plant-based milk alternatives out there. In fact, it comes in second in total sales (after almond milk) in the U.S. plant-based milk market.

Many prefer this because of its rich flavor, versatility, and neutral taste. If you can tolerate it, it’s often a good milk substitute for various reasons. It's helpful for lactose-intolerant people, people with nut allergies, those who follow a vegan diet, or anyone who just wants to reduce cow milk consumption.

Oat milk is used in everything from lattes to baked goods and even as a creamer in soups. But is it safe to drink every day? Does it have any potentially adverse health effects? What do we need to know about it?

In this article, we’ll explore what the research has to say about this trendy milk alternative and whether or not it’s a good option for blood sugar control.

The Origins of Plant-Based Milk

There are many reasons why plant-based milk has risen in popularity in recent years. They are a suitable alternative to cow’s milk for lactose intolerant people or vegans and have become a popular option to add to your morning cup of coffee.

However, you may be surprised to discover that some milk varieties have been around for centuries, originating as ingredients in Chinese and Indian cultures, among others.

Almond, coconut, and soy milk have been around since the 13th century, according to a book titled History of Soymilk and Other Non-Dairy Milks. These alternatives are thought to have originated in places like the Middle East and Asia. Oat milk, on the other hand, has only been around since the '90s and was invented in Sweden.

This cereal-based milk was developed as an alternative for those with nut or soy allergies and has quickly become one of the most common and trendy milk substitutes. Factors like the taste, price, environmental impact, and availability may all influence your individual preferences.

Health Benefits of Oat Milk

glass of oat milk

The consumption of oats has links to many health benefits, including a lowered risk of type 2 diabetes, cholesterol, and certain cancers.

Because oat milk is derived from oats, it also contains a type of soluble fiber called beta-glucan, which is known to support overall metabolic health and lower the risk of obesity.

In fact, one study among individuals who consumed oat milk rather than cow’s milk and other alternatives found that drinking oat milk might have contributed to lower LDL cholesterol  levels, though these are preliminary results in need of more clarification with additional studies.

While it appears that oat milk can be beneficial and packed with vitamins and minerals, every non-dairy milk option does have certain advantages and disadvantages.Here are some pros and cons of oat milk:


  • It has a thick consistency similar to cow’s milk.
  • It has a neutral taste.
  • It's got the highest fiber content of plant-based milk alternatives.
  • It’s one of the most sustainable plant-based milks as it is derived from oats.
  • It is lactose, nut, and soy free (for those with allergies) and suitable for vegans.


  • It may not be gluten-free (oatmeal can sometimes contain gluten, depending on its manufacturer). 
  • It contains maltose, which has a glycemic index of 105.
  • It includes the highest carbohydrate content among all plant-based milks due to the starches in oats (16 grams of carbohydrates per cup).
  • One cup of oat milk contains around seven grams of added sugars.
  • Some brands use artificial fillers and preservatives, which can have adverse health effects.
  • It doesn’t contain calcium (unless fortified).

How Does Oat Milk Affect Blood Sugar?

someone checking blood sugar

Now that we’ve identified a few benefits and potential drawbacks of oat milk, how does this drink affect blood sugar levels? Well, the answer is that a few factors may influence your glucose response.

Oat milk contains a type of sugar called maltose, which has a glycemic index of 105, which is even higher than pure glucose.

When oats are processed to create oat milk, enzymes are added to help break down the oat starch, causing these complex carbs to be broken down into quickly digestible simple carbs.

Even when unsweetened, oat milk contains natural sugars that may not be ideal for anyone looking to prevent blood sugar spikes. It’s important to note that not everyone will have the same reaction to certain foods and ingredients.

Consulting with a credentialed dietitian or medical professional can be helpful to make sure you’re choosing the right foods for your health.

One Nutrisense Member’s Experience

Meredith Standridge is a Nutrisense member who signed up for the 12-month Nutrisense CGM program. She was interested in seeing how her diet affected her glucose levels and finding new ways to work towards her weight loss goals.

During the year-long program, she was surprised to find that certain foods she regularly included in her diet spiked her glucose. Notably, she tested her blood sugar response to her morning coffee and was surprised to see how oat milk affected her levels.

As she told us, “Another weird thing that caused a significant spike was oat milk. I knew it had sugar, but I thought it was healthy for me. I tried almond milk next, which was much better for [my glucose levels].”


Using a CGM to Test Oat Milk Response

Using a continuous glucose monitor to track how your blood sugar responds to certain foods can help form new eating habits for better metabolic health. Natalie Krafft, a health writer on the Nutrisense team, decided to test how her body responded to a morning coffee with oat milk instead of a cup of black coffee.

With her CGM on, she drank a cup of 100 milliliters of coffee mixed with 50 milliliters of Oatly oat milk. Below, you can see that her blood sugar spiked up to 123 mg / dL shortly after drinking an oat milk coffee on an empty stomach.

glucose chart showing oat milk coffee

In contrast, a few days later, she drank a 150-milliliter cup of black coffee soon after waking up. This time, she found that her glucose levels remained almost unchanged after two hours, peaking at 74 mg / dL.

glucose chart showing black coffee

These findings are just one example of the different blood sugar responses that someone may have when consuming oat milk.

However, it’s important to remember that these levels may change with other factors. Some of these include the time of day you consume it or whether or not you drink your oat milk with or without sources of fiber or protein.

Other Non-Dairy Milk Alternatives to Consider

soy, almond, oat, coconut milk info

Because of its carbohydrate and sugar content, oat milk may not be the most glucose-friendly milk alternative for some people. This is especially true if you commonly opt for an oat milk latte first thing in the morning.

So, how do other milk alternatives compare? Let’s have a look at three other popular options.

different types of milk

1. Soy Milk

Soy milk, which originated hundreds of years ago in China, was once one of the most popular milk replacements for individuals who are lactose intolerant or allergic to milk proteins.

It's made from soybeans, rich in isoflavones and phytochemicals, and has the highest protein content of any milk alternative (seven grams of protein per cup). It may be a preferable alternative for morning consumption as it’s high in protein compared to other milk alternatives.

2. Almond Milk

The most popular milk alternative in the U.S. is almond milk. This is an ideal alternative to cow's milk, and is often fortified with essential vitamins and minerals such as vitamin E, calcium, zinc, iron, and phosphorus.

Although almonds contain heart-healthy monounsaturated fats, this milk alternative is generally lower in protein and higher in sugar. Make sure to opt for an unsweetened variety if including almond milk as your beverage.

3. Coconut Milk

Coconut milk is generally sold in a can. It is often used in curries, creamy pasta sauces, and other tasty recipes. This milk alternative can help lower cholesterol and is usually fortified to be contain some antioxidants, calcium, and vitamins D and B.

While the canned variety used in cooking is much higher in calories than other plant-based milk alternatives (450 calories per cup), some brands have developed lighter options (50 calories per cup) suitable for drinks such as coffee.

For anyone with chronically high blood sugar or hyperglycemia, coconut milk can be a great option as it’s been observed to help lower blood glucose levels.

Related Article

Read More

Engage with Your Blood Glucose Levels with Nutrisense

Your blood sugar levels can significantly impact how your body feels and functions. That’s why stable blood glucose levels can be an important factor in supporting overall wellbeing.

With Nutrisense, you’ll be able to track your blood glucose levels over time using a CGM, so you can make lifestyle choices that support healthy living.

When you join the Nutrisense CGM program, our team of credentialed dietitians and nutritionists are available for additional support and guidance to help you reach your goals.

Ready to take the first step? Start with our quiz to see how Nutrisense can support your health.

Find the right Nutrisense program    to help you discover and reach your health potential.
Heather Davis, MS, RDN, LDN

Reviewed by: Heather Davis, MS, RDN, LDN

Heather is a Registered and Licensed Dietitian Nutritionist (RDN, LDN), subject matter expert, and technical writer, with a master's degree in nutrition science from Bastyr University. She has a specialty in neuroendocrinology and has been working in the field of nutrition—including nutrition research, education, medical writing, and clinical integrative and functional nutrition—for over 15 years.