Is Your Protein Supplement Giving You an Upset Stomach?

Female cyclist aware of whey protein powder side effects is drinking liquid collagen from her sports bottle

Picture this: You just finished a KILLER workout.

You’re headed off the gym floor/track/road/bike, and ready to refuel with a satisfying whey protein shake. You need something to replenish your protein stores, give your muscles plenty of nutrients to build from, and calories to fill the empty gnawing in your stomach.

You make your shake and chug it down, only to experience abdominal pain and discomfort shortly after. Your protein shake may even go straight through you, leaving you dissatisfied and discouraged.

Did you even absorb the protein you needed?

When you have the right protein shake and drink it at the right time, you shouldn’t experience these churning protein powder side effects. Some athletes think it’s normal because it’s always happened to them, but this should not be the case. With the right protein, and by following a few protein shake guidelines, you should feel refueled and revitalized after a workout and not be running to the bathroom. 

If your whey protein is giving you an upset stomach, or you’re experiencing some common whey protein powder side effects, this article is going to guide you through the ins and outs of a good protein shake and how to drink it so you digest and absorb it properly (and without discomfort). 

Why Your Protein Shake May Be Giving You An Upset Stomach

First, let’s talk about a few reasons your post-workout protein shake may be causing an upset stomach. Even if you’re using a high-quality, digestible protein, the way you drink it may be causing trouble inside your digestive system.

You drink it too soon 

While you want to refuel soon after a workout, drinking your protein shake too soon can lead to digestive upset. When you work out, most of your body’s energy goes to supporting your muscles, limbs, and brain as they take you through your exercise routine. Your digestive system slows down to the bare minimum during challenging exercise. After you finish a workout, it takes some time for the digestive system to start up again. This means if you start eating or drinking right away, your stomach may not be ready. 

Waiting 30 minutes to take your post-workout protein is a good rule of thumb to ensure adequate time for your body to “settle down” and get back into rest-and-digest mode. 

You use too much protein powder

In the case of post-workout protein, more is not always better. If you had a particularly difficult workout, you may be tempted to add another scoop of powder to your post-workout shake. Protein is a difficult macronutrient for the body to digest, and if you take too much at once, it is almost guaranteed to cause digestive distress, especially after heavy exercise. 

Not only that but your body is only capable of digesting a certain amount of protein at a time (generally between 25-35 grams per meal). It’s important to be aware of your body’s protein absorption rate or you’ll just be wasting your money on a supplement you drink but don’t absorb properly. 

You drink it too quickly

It’s no surprise that after you finish a challenging workout, you’re hungry!

A liquid protein shake is easy to chug down rapidly. Doing this, however, can overwhelm your digestive system and cause your whey protein to give you an upset stomach. Not only that but when you drink something super quickly, you are likely also swallowing air. This can cause bloating and abdominal pain. 

To avoid feeling completely ravished after a workout, be sure to fuel up with a good pre-workout meal 1-2 hours before your exercise.

If you’re an endurance athlete, you may also consider consuming a highly-digestible electrolyte/protein supplement during your actual workout. This will keep your energy stores from being completely depleted during your workout and will likely help you reach your goals more easily.  

How to Choose The Right Post-Workout Protein Supplement

If you’re following all the guidelines above and still experiencing stomach duress after a workout, it may be time to look more closely at the type/brand of protein you are consuming. 

Whey protein powder side effects 

Whey protein is by far the most common type of protein athletes consume.

But is it the best option for you? Although whey protein does have benefits as a post-workout shake, it comes with a list of side effects for a large majority of users. 

  • Bloating
  • Gas
  • Stomach cramps
  • Diarrhea 
  • Stuffy nose

If using whey protein in place of whole food, (for weight loss), it may also increase one’s risk of nutritional deficiencies. Always be sure to consume a balanced diet with plenty of fruits and vegetables (even when trying to lose weight) to avoid nutritional deficits. 

Since these side effects are related to lactose intolerance or a milk allergy in some people, you may be able to avoid them by simply switching to a whey protein isolate or non-dairy protein alternative

Digestibility of your post-workout protein

As we discussed earlier, it takes some time for your body to come back to the “rest-and-digest” mode after a heavy workout.

For this reason, you want to use a protein supplement that is highly digestible and takes minimum effort for your body to absorb. Pure protein is the most difficult to absorb, which is why most companies do one of two things to increase bioavailability: use hydrolyzed protein or add digestive enzymes. 

What is hydrolyzed collagen protein?

You will most often find hydrolyzed protein in collagen supplements. When a protein molecule is hydrolyzed, it simply means it is broken down into smaller pieces so that your digestive system has less work to do before absorbing it and sending it off to be rebuilt by cells throughout your body. All proteins must be broken down by the digestive system anyway, so drinking hydrolyzed protein simply aids the digestive system in utilizing it more quickly. 

Because a collagen protein is such a massive molecule to begin with (contains over 1000 amino acids), the most effective collagen supplements always come in a hydrolyzed form.

Be sure to choose a high-quality brand that contains hydrolyzed collagen and is fortified with the 9 essential amino acids that make it a complete protein, like Frog Fuel Power

In an independent study done at Kennesaw State University, our nano-hydrolyzed liquid protein shots were found to be 100% digestible within only 15 minutes. This is in sharp contrast to a leading whey protein brand, which took much longer to digest (less than 1% was digested in the first 15 minutes after consumption). 

What are digestive enzymes?

Enzymes assist the body in breaking down the food it eats. They play a key role in digestion and absorption and are necessary for the body to receive all the nutrients it needs from the food you eat.

The body makes some enzymes on its own, and the rest come from eating whole foods or supplements containing digestive enzymes.

Some protein brands have realized that to increase the bioavailability of their protein, adding digestive enzymes is paramount. Always choose a protein supplement that contains digestive enzymes or is hydrolyzed. 

Other common types of protein

While collagen and whey protein are the most commonly used by athletes, there are other types of protein to consider based on your lifestyle and unique needs. Vegetarians and vegans, for example, generally choose a plant-based protein powder made from soy or other plant-protein sources. 

What Protein Supplement Is Right For Me?

When choosing a post-workout protein supplement, it is important to consider three things: digestibility, protein type, and accompanying ingredients. If you’ve had a lot of problems with digestive upset, you’ll also want to choose a good protein for a sensitive stomach. 

With digestibility, you want a protein that is easy on the digestive system and highly absorbable.

Your best bet is to go with a hydrolyzed protein supplement or one that contains high-quality digestive enzymes. 

Protein type will depend on your diet and lifestyle. For most athletes, a hydrolyzed collagen supplement is a great choice because collagen is specifically used by the body to rebuild connective tissues like ligaments, skin, and muscles. Visit our article on collagen protein versus whey protein to see why we recommend hydrolyzed collagen over whey for athletes.   

It is always important to view all the ingredients in your protein supplement so that you can avoid sugars, fillers, and harmful additives. You also want a supplement that is a complete protein, which means it contains all of the essential amino acids. Unlike Frog Fuel, most hydrolyzed collagen supplements are NOT fortified to be complete proteins so check the label for all 22 amino acids.

It can take some trial and error to find the right protein supplement for you. Don’t be discouraged if you have to go through a few brands before you find something that sits well with your unique digestive system.

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