Can You Put Oats In A Protein Shake? (6 Reasons Explained)

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You may have heard about people putting oats in a protein shake and wondered if and how to do it yourself.

So, can you put oats in a protein shake?  Yes, you can put oats in a protein shake.  Oats are a great way to add calories, carbohydrates, fiber, and micronutrients to your protein shake.  They can make protein shakes more filling and can be consumed whether your goal is to gain or lose weight.

I will cover reasons to put oats in a protein shake, who should put oats in a protein shake, and when and how to do it.  I’ll explain what kinds of oats work best and give you some great recipes.

6 Reasons to Put Oats In A Protein Shake

pros vs cons of putting oats in a protein shake

1. High In Protein & A Source of Gluten-Free Carbs

Oats are an excellent gluten-free source of carbohydrates.  They are higher in protein than many other grains, and they are a good source of fiber.

One half-cup (40g) of dried rolled oats has the following nutritional content:

  • Calories: 150
  • Carbs: 27g (4g fiber; 1g sugar; 0g added sugar)
  • Fat: 3g
  • Protein: 5g
  • Sodium: 0mg

2. Oats Are Full of Micronutrients & Antioxidants

As a gluten-free grain, oats are suitable for celiac diets, and the type and amount of fiber in oats are beneficial for gastrointestinal problems and for heart health, with oat fiber shown to reduce blood cholesterol levels.

Check out a list of micronutrients in oats by Recommended Daily Allowance (RDA) per 40g serving and their benefits:

  • Manganese 86% RDA: supports a healthy metabolism and can help to reduce inflammation, which can ease soreness from exercise.
  • Copper 28% RDA: helps your body to make red blood cells and collagen, important for the health of your connective tissues which are so important to moving well. Copper also assists in the absorption of iron. 
  • Thiamin (B1) 26% RDA: helps with converting food to energy and with cell repair.  Vitamin B1 is important for cognitive function by supporting the brain and the central nervous system.
  • Phosphorus 21% RDA: works with calcium to form strong bones.  Phosphorus is also key in how the body stores and uses energy and can reduce muscle pain after exercise.
  • Magnesium 17% RDA: is a key mineral for all organs in the body, assisting with metabolism, digestive health, sleep and recovery from both training and life in general.
  • Zinc 11% RDA: assists with blood clotting and has an important role in the immune system, along with assisting with thyroid function.  These aspects make it important for recovery from training and for ensuring a healthy metabolism.  
  • Pantothenic acid (B5) 11%: helps turn the food you eat into the energy you need.
  • Iron 10% RDA: is an important component of red blood cells, carrying oxygen-rich blood to all cells of the body and assisting in the production of energy.  Iron can assist in sports performance.

3. Oats Mixed With Protein Is A Convenient Meal

Oats are very easy to add to protein shakes.  Packets of plain instant oatmeal are a great portable, pre-portioned option.  

You do not have to cook oats before adding them to a protein shake.  

However, soaking them first will make them easier to blend and improve their digestibility (more on this later).  

4. Oats Are Versatile

On their own, oats have a very mild taste which means that they will mix easily with whatever other flavors you want.

We recommend in our article how to make vanilla protein powder taste better to mix it with oatmeal.

5. Oats & Protein Can Aid With  Weight Loss Goals

If your goal is weight loss, adding oats to a protein shake will make it more satiating.  Feeling full for longer will help you to manage your appetite over the course of the day.  This will make it easier to stick to a calorie deficit needed for weight loss.

However, because the oats will also add calories, it is important to track them as part of your overall intake.

You can track your macros using an app like MacroFactor. Using this link gets you an extra week on your free trial (2 weeks total). Cancel any time before your trial ends without being charged.

6. Oats & Protein Can Aid With Weight Gain Goals

If your goal is weight gain, adding oats to a protein shake will add more calories and carbohydrates without requiring you to have an extra meal or snack.  This can help you to increase your intake over the course of the day without feeling like you are eating all the time.

The only difference between weight loss and weight gain goals when it comes to adding oats to protein shakes is the portion size.  For weight gain, you’ll be adding more oats than for weight loss goals.

However, because oats have a lot of fiber, they can be quite filling and you will not feel hungry again for a while. Individuals looking to gain weight should also consider faster-digesting sources of carbohydrates such as dried and fresh fruits.

  • Dried fruit (dates, raisins, prunes, dried dates, dried figs, dried apricots)
  • Mango 
  • Pineapple
  • Oranges
  • Grapes

Check out: How To Gain Weight Without Eating Sugar (Sample Meal Plan).

Who Should Not Mix Oats With Protein Shakes?

Who should not mix oats with protein shakes?

There are a few cases where oats are not a good idea to add to protein shakes:


It is possible to be allergic to oatsAnyone with an oat allergy should avoid oats in all forms.

Gastric Distress

The high fiber content in oats can cause abdominal bloating, cramps and flatulence.  These symptoms can be eased by soaking or cooking the oats in water before adding them to protein shakes to enhance digestibility.  However, if uncomfortable symptoms persist, then oats should not be added.

Inability To Meet Target Calories

For Weight Loss:

For some individuals, drinking calories does not provide a sense of fullness, even if there is a high fiber content.  They feel hungry again very soon, making it hard to manage a calorie deficit.  

Studies show that chewing food can reduce energy intake and increase satietyIn this case, it is better to focus on chewing and eating whole foods rather than having liquid calories of any kind, including protein shakes.   

For Weight Gain:

For some individuals, the fiber content in oats makes them feel uncomfortably full.  This makes it harder for them to finish a protein shake with oats, and also means that they will not be hungry again for several hours, making it harder to reach a calorie surplus needed for weight gain.  

In this case, it is better to add faster-digesting carbohydrates including simple sugars.  These can come from fruits or fruit juices or refined sources of sugar.

Paleo Diet or Keto Diet

The Paleo Diet eliminates ALL grains, including oats.  Individuals following the Paleo diet cannot add oats to a protein shake.

Oats are too high in carbohydrates for the Keto diet.  Individuals following the Keto diet cannot add oats to a protein shake.

Note that our team of nutrition coaches and Registered Dieticians at FeastGood does not generally recommend eating approaches/diets that restrict or remove entire categories of food, except in special, medically-necessary circumstances.

If you’d like a free one-on-one consultation with one of our coaches, check out our coaching services page.  

When To Have Oats In A Protein Shake

when to have oats in a protein shake

The best time to have oats in a protein shake is post-workout, as part of glycogen replenishment.  Oats can provide some or all of the carbohydrates needed to provide a 2 to 1 carbs to protein ratio.

For example, a protein shake with 1 scoop of protein powder providing 25g of protein could include up to 1 cup (80g) of oats providing 54g of carbohydrates.  

Oats are too high in fiber to provide the quick energy needed for an immediate pre-workout snack.  

Because of their long-lasting energy, a protein shake with oats can also replace a meal at any other time of the day.  This makes a convenient, portable option with minimal preparation time and dishes.  This is very appealing for people with time constraints.

A protein shake with oats can also provide supplemental calories when served alongside a meal for individuals looking to gain weight. 

How To Mix Oats In A Protein Shake

The best way to mix oats into a protein shake will depend on the amount of planning and preparation you can and want to do vs. convenience.

For optimal digestibility and nutrient absorption, the best way to include oats in a protein shake is to use fully cooked, cooled oats that are added to the other ingredients in a blender.  

Tips for Cooking Oats

  • Cooking oats requires 1 part oats for 2 parts liquid (e.g. half cup oats and one cup of water).  Bring the water to a boil and stir in the oats.  Reduce heat to low and stir occasionally for 3-5 minutes.  
  • To cook oats in the microwave, combine the oats and water in a microwave-safe container and heat on full power in 30-second increments, stirring in between until desired consistency is reached.
  • You can replace the water with almond milk or dairy milk to add more calories.

A no-cook option is to soak the raw oats, at least 30 minutes or up to overnight.  Soak the oats with 1 part oats to 2 parts liquid (water, milk or almond milk).  This softens the oats similar to cooking, making them easier to blend and to digest.

If you do not have time to cook or soak the oats, you can also grind the oats into a powder using a coffee grinder.  Some blenders also have a setting for dry goods like oats.  It’s also possible to purchase oat flour or ultra-fine oats.

You can add ground oats, oat flour, or ultra-fine oats along with the protein powder in a protein smoothie.  Be sure to add at least 2 measures of liquid for each measure of oats to avoid a too-thick texture.

If you cannot cook, soak or grind the oats, use instant oats.  Follow the same method as for ground oats.

What Kind Of Oats To Use For Protein Shakes?

What kind of oats to use for protein shakes?

The very best kind of oats to use for protein shakes is fully cooked and cooled sprouted rolled oats.  Sprouted oats have been prompted to germinate, a process that increases nutrient availability and makes them easier to digest.  

If you do not have time to cook, soaked sprouted rolled oats are next.  If you do not have sprouted rolled oats, regular rolled oats also work.  

If you do not have time to soak, oat flour (homemade or store-bought) is next.

Finally, the fastest option is to use packets of instant oats.

What Is The Best Type of Protein To Mix With Oats?

The best type of protein powder to mix with oats is your preferred protein powder for protein shakes.  I personally use and recommend a whey isolate protein powder (Diesel New Zealand Whey Isolate).

If you would prefer to stir protein powder into a bowl of cooked oatmeal instead of a shake, be sure to add whey protein powder at the end, else it will create a gummy texture.  

Plant-based protein powders (like Sunwarrior Classic Brown Rice Protein) have a more pleasant texture when added to cooked oatmeal.

Protein Shake & Oats Recipes

One of my favorite recipes for a protein shake with oatmeal is:

The “Sticky Toffee” Protein Smoothie

sticky toffee protein smoothie

Cook or soak the oats in the water for up to 30 minutes before making the shake to allow them to blend more easily.  Then, combine the ingredients in the order listed in a high-speed blender and process until smooth.  Calories/macros will depend on the exact ingredients and amounts used.

  • With water and 2 dates: Calories 350 (33P-50C-3F)
  • With 2% milk and 3 dates: Calories 525 (41P-73C-8F)

Or try these recipes from the web:

Looking for more oatmeal recipes, check out these 9 Best High-Protein Bodybuilding Oatmeal Recipes

Other Ways to Mix Oats With Protein Powder

Protein shakes and smoothies are not the only way to have oats with protein powder.  You can also make oatmeal with protein powder stirred in at the end, or make a protein pancake with oatmeal.  You can even bake oatmeal cookies with protein powder.

About The Author

Lauren Graham

Lauren Graham is a Precision Nutrition Level 1 certified nutrition coach. She focuses on helping busy professionals balance healthy eating and purposeful movement.  Lauren has a background in competitive swimming and is currently competing as a CrossFit athlete.  She has a passion for training, teaching, and writing. 

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