Avoiding the “Too Much Protein Stomach Ache”

Cyclist, now on collagen to prevent whey protein stomach ache, is pedaling with intensity and determination


Is your post-workout protein shake causing you grief? If you’ve regularly found yourself in discomfort after your protein supplement, you may be wondering: “Can too much protein cause a stomach ache?” If so, how can you go about avoiding a too much protein stomach ache?

If that’s what you’re thinking right now, you’re certainly not alone. Whey protein stomach aches are a common complaint, but it’s not a necessary side effect of taking protein supplements.

Like anything with this much potential gain, there’s a right way and a wrong way to go about your supplementation:

Use protein supplements properly and they may give you that edge you’re looking for on the field or in the weight room. 

Use them incorrectly, and you may be facing a too much protein stomach ache, which will make you much more reluctant to continue with your training for the day.

So let’s get into answering “why does protein powder make my stomach hurt?” Then, we’ll discuss the best types of protein supplements to take to avoid a too much protein stomach ache. 

What causes a too much protein stomach ache?

Too much protein can (and does) cause stomach aches - it’s often cited as one of the cons of protein powder - but it is by no means necessary to experience stomach aches with protein supplementation.

When taking the right supplements in the right amounts, you should absolutely be able to avoid a too much protein stomach ache. But you’re probably wondering, “why does protein powder make my stomach hurt in the first place?”

There are multiple reasons your supplement could be causing you grief, and they may come as a surprise to you. Here are some of the most common causes of stomach aches from protein supplements.

1. Ingesting too much protein

When you take a protein supplement, it heads straight to your stomach for digestion, just like any other food you eat. The stomach’s goal is to use stomach acid to break down the molecules you digest into particles so small that they can be absorbed into the bloodstream safely.

Too much protein causes stomach aches because the stomach has a big role to play in protein synthesis, which is often a delicate process. Proteins are divisible and digestible in themselves. When you ingest a protein supplement, your body breaks the protein down into amino acids.

Amino acids are the building blocks of protein, and they become part of a pool from which your body can call on to synthesize new collagen fibers for strengthening muscle mass or healing wounds.

Research has shown that it takes the body 90 minutes to digest viscous liquids like protein shakes. Not only that, but the body can only digest 8-10 grams of whey protein every hour - which begs serious questions about how much protein is actually being absorbed.

A too much protein stomach ache can be caused when you are ingesting more protein than your body can reasonably digest. That’s why it’s important to read the directions on your supplement packaging, 

It’s also vital to do your own research into proper supplementation amounts - as most supplements are FDA regulated, and the company you are purchasing from may or may not be reliable. 

Not all protein supplements are created equally, and some are more difficult to digest than others. If you take too much protein at once, and the molecule size of your supplement is difficult for your body to break down, you might end up with bloating and a stomach ache because of it.

Which leads us to our next topic: molecule size.

2. The molecule size of your supplement

Want to avoid too much protein collagen stomach aches? Stick to proteins that are easily digestible. 

How do you know which ones those are?

If you don’t want your protein powder to cause a stomach ache, you need to look for protein molecules with a smaller size so they can be more easily accepted into the bloodstream. 

This is one of the reasons why a whey protein upset stomach is a common complaint; the size and characteristics of the molecule that needs to be digested.

In its whole form, most protein molecules are the easiest to digest. That’s why it’s important to look for supplements that have gone through the process of hydrolysis, such as hydrolyzed collagen protein.

Hydrolysis uses water at high pressure to break down the size of collections of protein molecules. This process makes your supplement much more bioavailable and less likely to cause stomach upset.

The best thing is, you can put a protein molecule through hydrolysis more than once. Such a product would be called “nano-hydrolyzed.”

Just how effective is this process? Take a look at this:


Frog Fuel's Nano Hydrolyzed Collagen vs Whey Isolate and other Collagen Products

Looking at the relative sizes of the molecules that need to be absorbed, it’s clear how nano-hydrolyzed collagen like FrogFuel liquid protein is much less likely to contribute to a too much protein stomach ache.

Of course, it’s not just the amount of supplement, nor the molecule size, that causes issues for people. A too much protein stomach ache might be a misnomer if the type of protein you’re taking isn’t right for you.

3. The type of protein supplement you’re taking

Are all proteins fundamentally the same? Absolutely not.

Enzymes are proteins, antibodies are proteins, and even some hormones are proteins. Most visibly however, proteins give structure and form to muscles.

With such a high demand for protein all over the body it may come as a surprise that too much protein causes stomach aches, but everything in the body needs to be kept in balance. That’s true for the types of proteins the body works with at any given time. 

All protein supplements have their place and their respective pros for the body, but are they all as likely to leave you with a too much protein stomach ache? To answer that question, we need to see how easy each type of protein is to digest.

Often, the choice on which protein supplement works best for you involves doing the research on collagen protein vs whey protein, but casein protein is also a popular choice for supplements. Let’s take a look at the three to see how they can benefit (or potentially harm) your body. 

Collagen protein

Let’s start with the most abundant protein in the body - collagen protein. 

Your body is creating, synthesizing, and utilizing collagen on a constant basis. Sadly, the body naturally slows down generating its own collagen as we get older, which is why it is such a popular protein supplement.

What does collagen do? 

Collagen really comes into the fore when we’re healing from wounds and repairing our skin and blood vessels. In fact, it’s so good at that job that as a protein supplement it got pigeonholed into the skincare and wound healing category. 

Collagen supplements, when they’re from a reliable source, are medical-grade go-to treatment options in hospitals across the United States. But actually, the uses of collagen protein supplements stretch much further than that.

Athletes should be paying attention to collagen because collagen reinforces tendons and ligaments

The tendons and ligaments in your joints are the connection pieces between muscle and skeleton. No joints = no movement. 

80% of the dry weight of ligaments is collagen protein. Athletes do not need to be told twice about how entire careers are built on the ability to avoid injury to important but fragile tendons and ligaments. 

Because collagen is so abundant in your body, it is safe to supplement with. In fact, as long as you are paying attention to the amount and molecule size of your supplement, it is much less likely to cause a too much protein stomach ache than some other popular protein options.

Whey protein

Whey is often the go-to supplement for building up muscle size and raw strength. It’s incredibly popular with gym-goers who’re looking to bulk up their bodies.

Athletes who are starting out often prioritize bulk over everything else, so they overdo their supplementation and get a too much protein stomach ache. 

While whey bulks out muscle, many supporters also take it because of its potential to help you lose weight by boosting your metabolism and reducing your appetite. Although these results might be what some people are looking for to help them diet, others believe taking too much protein and getting a stomach ache isn’t worth it just to disguise a hunger craving.

Whey is certainly worth looking into, but if you already know how a whey protein stomach ache feels, then it’ll be good news to hear that it isn’t your only protein supplement option. 

Why is whey protein a common culprit of stomach aches? One reason is that it is made from dairy products. Many people have some degree of lactose intolerance without even being aware of it, so if you find yourself suffering from whey protein stomach aches, it may be worth switching supplements.

Casein protein

Casein protein is also found in milk, and it’s actually the substance that gives milk its white color. Caseins can be considered as a calcium delivery package. They help calcium get to where it needs to go, strengthening teeth and bones.

Most of all however, casein is considered a “time release” protein because it takes much longer to digest than whey. The amino acids it contains are of use for rebuilding muscle mass after a strenuous workout.

Slower to act than whey or collagen, casein trickles through your gut and has a slower absorption rate into the bloodstream. Its larger molecule size means your stomach works harder to process it. 

Although some consider this an advantage as it lowers metabolism, others claim it overworks their stomach and causes too much protein stomach aches. In fact, of the three proteins mentioned, the difficult digestibility and dairy origin will make casein protein the most likely culprit for stomach issues.

The problem with lactose

Whey and casein proteins are both lactose products found in milk and dairy. For any athletes with a full or partial lactose intolerance, taking whey or casein protein is going to provoke the same sort of negative side effects as drinking milk. 

Lactose intolerance could be a very simple answer to the question, “why does my protein powder make my stomach hurt?” 

Whey and casein protein are commonly distanced from being marketed as the dairy products that they are, in favor of their potential bulking gains as protein supplements. Athletes and non-athletes who avoid dairy should also steer clear of whey or casein protein supplements.

Importantly, once again, collagen naturally avoids the stomach ache red flags. Collagen is not a lactose product and so it is suitable for lactose-intolerant athletes. Collagen also makes a great protein powder for sensitive stomachs.

The best collagen supplements to avoid stomach upset 

If you don’t want to deal with a too much protein stomach ache, it’s best to search for collagen supplements that are hydrolyzed or nano-hydrolyzed and come from a trusted source. 

Frog Fuel liquid collagen protein is made from a formula that is trusted by doctors and athletes alike all over the USA. With a convenient liquid form, nano-hydrolyzed molecules, and no added preservatives or sweeteners, Frog Fuel collagen supplement is a safe bet for athletes with sensitive stomachs. 

The pouches could not be more convenient, as they each contain 15g of liquid protein. That’s enough to fuel you through your strenuous workout, without causing a strain on your stomach. In fact, Frog Fuel is proven for 100% digestibility in less than 15 minutes

If you’re prone to too much protein stomach aches, why not make the switch to Frog Fuel liquid collagen protein to see the difference for yourself.

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