What causes protein shake diarrhea? 

Discover what causes protein shake diarrhea and how to avoid this common side effect. Learn how to supplement your protein intake without causing digestive issues.

Protein shakes and diarrhea

Can protein shakes cause diarrhea?

If you find yourself rushing to the bathroom after drinking a protein shake, you are not alone.

Many people experience what commonly known as protein shake diarrhea, or loose and watery bowel movements shortly after consuming a protein shake.

While these symptoms typically subside within a few hours, some folks have reported dealing with protein shake diarrhea for several days.

The good news is that despite being a common side effect, protein shake diarrhea is entirely avoidable.

Keep reading to learn how to pick a protein supplement that will not cause diarrhea.

How do I avoid protein shake diarrhea?

Here are the ingredients that, when avoided, significantly decrease the likelihood of protein shake diarrhea and other digestive issues:

Avoid food additives

Food additives like emulsifiers, thickeners, and flavors tend to draw water into the colon, thereby increasing the liquid content of the stool. This happens because additives are hard to digest and create something called a high osmotic load.

When the osmotic load is high, there is more osmotic pressure, which is the pressure exerted by a solvent (usually water) as it moves across a semipermeable membrane (in this case the colon) in order to balance the concentration of solutes on each side of the membrane. 

Here is a list of the most common food additives in protein supplements:

• acacia fiber
• acacia gum
• acesulfame potassium
• artificial flavors
• ascorbic acid
• aspartame
• calcium carbonate
• carrageenan
• cellulose gum
• dextrin
• dicalcium phosphate
• dipotassium phosphate
• erythritol
• gellan gum
• guar gum
• gum arabic
• inulin
• locust bean gum
• maltitol
• maltodextrin
• mono- and diglycerides
• ‘natural’ flavors
• rice bran extract
• rice dextrin
• rice hulls
• rosemary extract
• silica
• silicon dioxide
• sodium alginate
• soluble corn fiber
• sorbitol
• soy lecithin
• sucralose
• sunflower lecithin
• tocopherols
• tricalcium phosphate
• xanthan gum
• xylitol
• zinc oxide

Avoid dairy-based proteins

Dairy-based proteins like whey and casein can cause protein shake diarrhea because they contain lactose, a sugar most adults cannot fully digest.

Avoid protein concentrates and isolates

Most protein supplements are made from protein concentrates and isolates, which have been mechanically and/or chemically stripped of everything but the protein, including the enzymes, fiber, and other natural digestive aids that help you break them down.

Your digestive system therefore does not digest them in the same way that it does whole foods, which could lead to diarrhea.

Avoid artificial sweeteners and sugar alcohols

Artificial sweeteners and sugar alcohols also resist digestion and can therefore have a laxative effect. Common artificial sweeteners include sucralose and acesulfame potassium. Common sugar alcohols include erythritol, sorbitol, and xylitol. 

Limit insoluble fiber intake

Insoluble fiber adds bulk to the stool, so if you eat a lot of it at once, it can cause diarrhea. Most vegan protein supplements naturally contain insoluble fiber.

Some protein shakes and powders, especially those intended to help with weight loss, contain added insoluble fiber. These are what you really need to look out for as the added fiber they use is usually guar gum or inulin, which also happen to be used as laxatives! 

Be mindful of preexisting gut issues

When you eat dietary protein, it enters the stomach where stomach acid and enzymes start to break it down into smaller components. From there, the partially digested proteins move to the small intestine, where enzymes called proteases break them down into amino acids. Amino acids are then absorbed through the intestinal lining and enter the bloodstream, which transports them throughout the body.

If any part of this complex process is not working properly due to preexisting gut issues, then the protein you eat will not be fully broken down and absorbed. Not only will this deprive you of the amino acids you need to stay strong and healthy, but it can also cause painful side effects like diarrhea.

What should you do if you have protein shake diarrhea?

If you have diarrhea after drinking a protein shake, there are several steps you can take to manage it:

Stay hydrated

Diarrhea can lead to dehydration due to fluid loss. Drink plenty of clear fluids and avoid caffeinated and alcoholic beverages.

Eat bland foods

Stick to bland, easily digestible foods such as bananas and rice. These foods can help firm up stools without aggravating your stomach.

Rest

Give your body time to recover by getting plenty of rest. Avoid strenuous activities that can further deplete your energy levels.

Seek medical attention if necessary

If your diarrhea persists for more than a couple of days, you should consult a healthcare professional. They can help determine the underlying cause and provide appropriate treatment. Similarly, while managing protein shake diarrhea at home, it is essential to monitor your symptoms closely and seek medical advice if you are unsure about the best course of action.

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Drink Wholesome does not cause diarrhea.

Finding a protein powder free from food additives, dairy-based proteins, and protein concentrates and isolates is hard.

In fact, 99% of protein supplements contain one or more of these problematic ingredients, which is why we created Drink Wholesome.

Our protein powder does not cause diarrhea because we use a short list of simple ingredients.

Our Ingredients

egg whites

coconut

vanilla

monk fruit

NOT Our Ingredients

• acacia gum

• acesulfame potassium

• artificial flavors

• carrageenan

• erythritol

• guar gum

• inulin

• maltodextrin

• 'natural' flavors

• silica

• soy lecithin

• sucralose

• xanthan gum

• xylitol

Note that instead of using protein concentrates or isolates, we use whole food protein sources like egg whites and almonds, which are easier to digest and absorb.

It follows that our customers experience fewer digestive issues with our protein powder than with any other type of protein supplement. Order samples to see for yourself.