Debunking the Myth: Can Protein Shakes Cause Constipation?

Protein shakes are an effective way to support muscle growth and strengthening both pre- and post-exercise. That’s because the amino acids present in protein shakes — which include leucine, isoleucine and valine — are essential for muscle repair and synthesis. They also play a crucial role in preventing muscle breakdown. 

Depending on the type of protein, powders can contain far more than amino acids, however. Some contain lactose, which can disrupt digestion in certain people who are intolerant to sugar. Others contain digestive enzymes to support breakdown and digestion. 

That said, can protein shakes make you constipated? Protein shakes are unlikely to cause constipation. Although, a high-protein, low-fiber diet without sufficient water intake may cause irregular bowel movements. 

Understanding Protein Shakes

Protein shakes have gained significant popularity as a convenient and effective way or weight loss support and as a protein supplement. These beverages are commonly used by athletes, fitness enthusiasts and individuals seeking to support muscle recovery and growth.

The beverages are designed to provide a concentrated source of protein and typically consist of protein powder that’s mixed with a liquid, such as:

• Water
• Milk
• Plant-based milk alternatives

That said, protein shakes contain a variety of ingredients, with the primary component being the protein source itself. The most common types of protein powder used in protein shakes include:

• Whey protein powder – Whey protein, which is extracted from milk, is considered a complete protein as it contains all the essential amino acids necessary for the body. It’s known for its fast absorption rate, making it a favored choice among individuals seeking post-workout recovery.
• Casein protein powder – Another type of protein derived from milk, casein protein, digests at a slower pace, resulting in a gradual release of amino acids over an extended period. This characteristic makes it a popular option for those looking to support muscle recovery during sleep or overnight.
• Plant-based protein powder – Plant-based protein sources, like pea, soy and rice protein, have gained popularity among individuals who follow vegetarian or vegan diets. These alternatives to animal-based proteins offer essential amino acids and cater to individuals with dietary restrictions, such as lactose intolerance.

The Connection Between Protein and Constipation

As stated, protein shakes are often made from whey, casein or plant-based proteins and are generally well-tolerated by most people. To that end, they’re unlikely to cause constipation. Constipation is more likely to occur when there is a lack of dietary fiber or inadequate hydration as a result of, or in addition to, high protein intake.

Lack of Dietary Fiber

Fiber is found in many fruits, vegetables and grains. However, when consumed, the fiber is not absorbed during digestion.

Rather, insoluble fiber (whole grains, nuts and seeds) will pass from the small intestine to the large intensive to be expelled as stool, instead of entering the bloodstream with other nutrients. Soluble fiber (such as fruits and vegetables) can create a gel-like substance in the digestive tract to soften stool and move waste through the digestive system to support regular bowel movements. 

While a low-fiber diet does not equate to constipation, it may be a likely cause. This type of meal plan can limit the types of food you consume, including:

• Nuts and seeds
• Fruits
• Vegetables
• Whole grains
• Popcorn
• Rice
• Oats
• Grains
• Legumes

By incorporating enough of these foods in your diet, you can help support healthy digestion and may also help prevent constipation. That said, while dietary fiber can increase fecal matter, it’s not necessarily a cure for constipation. If you’re having difficulty passing stools or experiencing constipation, it's important to consider other factors and consult with a healthcare professional. 

In some cases, underlying medical conditions, medication side effects, inadequate fluid intake or a lack of physical activity may contribute to constipation.

Inadequate Hydration

Drinking eight to 10 glasses of water a day can help prevent constipation by softening stool and making it easier to pass. Accordingly, it’s believed that inadequate hydration may actually lead to constipation. 

In fact, dehydration is one of the most common causes of constipation. If your body does not have enough water, the large intestine will take the water from the food you consume, instead — effectively creating hard stools that are difficult to pass. 

High Protein Intake

Do protein shakes cause constipation? If you consume protein shakes as a part of a high-protein diet and neglect to drink sufficient water or consume enough dietary fiber, they can potentially lead to constipation.

While there is no strict definition, a high-protein diet typically involves increasing protein intake to a level higher than the recommended daily allowance (RDA), which is around 0.8 grams of protein per kilogram of body weight (or about 0.36 grams of protein per pound).

High-protein diets are often followed by individuals who are looking to build muscle, support athletic performance or lose body weight and will include:

• Eggs
• Lean meats, such as chicken, turkey, beef and pork
• Seafood, such as fish, shrimp and oysters
• Dairy products, such as milk, yogurt and cheese
• Legumes, such as beans and lentils
• Nuts and seeds
• Whole grains

Essentially, people following a high-protein diet will typically prioritize animal products over dietary fiber, which can cause both diarrhea and constipation. It’s also important to pay attention to the type of protein powder you use: Those with artificial sweeteners, stevia and sugar alcohols can cause gastrointestinal issues, such as constipation and digestive problems. Additionally, whey protein concentrate can contain lactose, since it comes from milk. People with dairy intolerances may find it more difficult to digest this type of protein, which can lead to digestive discomfort and irregular stools. And, in about one-third of cases, constipation can also occur. 

How to Prevent Constipation While Drinking Protein Shakes

To prevent constipation while consuming protein shakes, you can follow these strategies:

• Increase dietary fiber – As stated, incorporating enough fiber into your diet can help soften stools and make them easier to pass. To balance your diet, mix fruits, vegetables and whole grains into your protein shake, or find an organic superfood powder that already has green veggies and a digestive enzyme complex in its ingredients list.
• Stay hydrated – High protein intake can lead to dehydration and, sometimes, constipation. Additionally, in one study, it was found that student-athletes on high-protein diets also had limited kidney function compared to student-athletes eating a low-to-moderate amount of protein. As such, it’s believed that more water intake is needed to support the kidneys for those partaking in high-protein practices. To sufficiently hydrate your body and support its overall health, make sure to drink at least eight cups of water a day.
• Gradually increase protein intake – If you're increasing your protein intake significantly, do it gradually over time. Sudden and drastic changes in protein consumption may disrupt the digestive system and potentially lead to constipation. Also, give your body time to adjust by monitoring the portion sizes of your protein shakes to ensure you’re getting enough essential nutrients, too. 
• Stay active – Regular exercise can help support your digestive health and regular bowel movements to prevent constipation, which may occur as a result of inactivity. More specifically, exercise can increase the rate at which food moves through your stomach and intestines and can help stimulate and contract the muscles in your intestines to help you pass stools more easily. 

In addition to the protein source, protein shakes may include other ingredients, such as flavorings, sweeteners, vitamins and minerals. It’s important to read the labels and select protein shakes that align with individual dietary preferences and nutritional needs.

Benefits of Protein Shakes

Protein shakes offer a range of benefits when it comes to promoting muscle recovery and growth, as well as everyday health. These advantages include:

• Muscle protein synthesis (MPS) – Protein shakes deliver a concentrated supply of amino acids that are readily available for muscle protein synthesis. This crucial process aids in the repair and reconstruction of damaged muscle tissues, facilitating recovery after demanding workouts.
• Nutrient intake – By drinking protein shakes, you gain better control over your protein consumption, ensuring that you meet your daily protein requirements. This level of control proves especially advantageous for athletes and individuals with heightened protein needs.
• Convenience – Protein shakes are a quick and hassle-free option, perfect for individuals leading busy lives. They can be easily prepared and consumed post-workout or as a convenient snack between meals, providing a practical solution for on-the-go nutrition.

All-in-One Protein Shakes at INVIGOR8

Do protein shakes constipate you? No, but prioritizing a high-protein diet that’s lacking in dietary fiber and proper hydration can cause gastrointestinal issues and difficulty passing stool. That said, when incorporating a protein shake into your day-to-day, it’s critical to find a well-rounded protein powder that supports full body health, in addition to muscle growth and recovery.

At INVIGOR8, our All-in-One Superfood Shake is crafted with natural protein powder ingredients and eight nutritional complexes to ensure your diet is well-rounded:

• Total protein complex, with premium grass-fed whey protein
• Prebiotic fiber complex, with chicory root extract to help prevent constipation
• Green veggie complex, with chlorella algae, alfalfa grass, spinach leaf, kale leaf and broccoli head
• Essential fatty acid complex, with flaxseed, chia seed and coconut
• Digestive complex enzyme, with amylase, lactase, neutral protease, lipase, bromelain and papain
• Immunity support complex, with bovine colostrum
• Cognitive complex, with L-theanine and bacopa monnieri
• Probiotic complex, with lactobacillus acidophilus and bifidobacterium bifidum

For total body support, choose INVIGOR8.

Sources:

Mayo Clinic. Low-fiber diet do's and don'ts

CRUK. Diet, fluid and exercise

WebMD. How Drinking Fluids Can Help You Manage Constipation

Harvard Health. How much protein do you need every day?

VeryWellFit. Why Higher Consumption of Protein Requires More Water

WebMD. Exercise to Ease Constipation

Healthline. The 7 Best Types of Protein Powder