Can Meal Replacement Shakes Cause Constipation? | SOLUTIONS

Can Meal Replacement Shakes Cause Constipation

A meal replacement shake is a great way to cut the junk out of your food and eat clean and healthy. However, not all meal replacement shakes are made the same, with some containing ingredients that could interfere with your bowel movements. Therefore, the question is, can meal replacement shakes cause constipation?

Meal replacement shakes can cause constipation as they contain little to no dietary fiber. They usually have protein, gluten, or lactose in higher amounts, which are not pro-digestion ingredients. If the shakes are accompanied by poor fluid intake, constipation becomes very likely.

Continue reading to learn the reasons why meal replacement shakes are likely to cause bowel troubles and how adding more fiber to your food would help.

Reasons Why Meal Replacement Shakes Cause Constipation

There are different reasons why your meal replacement drink could have elongated your bathroom breaks. Here are some of the major ones:

Milk Protein

Generally, meal replacement shakes use casein or whey as their protein source. For the unaware, these proteins are by-products of the cheesemaking process.

Whey is the liquid that remains after milk undergoes curdling and straining.

Casein is a form of protein precipitated by the workings of rennet enzymes. The coagulum formed is packed with casein proteins, whey, lactose, fat, and several minerals.

Generally, proteins digest slower in the stomach than carbohydrates, with milk proteins being the slowest of their kind when it comes to digestion.

Casein proteins are milk-soluble but turn into insoluble curds upon entering your stomach, making it difficult for your digestive enzymes to assimilate or break them apart.

Lactose Indigestion

Since both casein and whey are milk by-products, they naturally contain lactose. The human body doesn’t naturally make lactase, the enzyme needed for lactose digestion. Though not all humans are lactose intolerant, almost all of them have an intolerance to the disaccharide to an extent.

When the lactose enters your bowel system, your body has zero clues on how to deal with it, invariably slowing down things in your digestive system. This leads to a condition called lactose intolerance.

Besides constipation, digestive disorder could also cause nausea, light-headedness, or vomiting.

Supplementing your whey and casein protein intake with some lactase enzyme supplements or switching to brown rice, pea, hemp, or non-dairy protein shakes could help prevent this intolerance problem from arising.

Ensure that the whey protein in your meal replacement shake is of the isolate variety and is not a concentrate. Compared to whey isolates, the concentrate variety is not as refined, which means higher lactose amounts.

Gluten Intolerance

In some individuals, the bowels cannot tolerate gluten, a group of proteins found in multiple grains. Gluten issues could also cause celiac disease, a condition that causes digestion problems.

If you are lactose intolerant, you must steer clear of dairy-based meal replacement shakes. If you have gluten intolerance or allergy, protein shakes based on non-dairy items such as wheat, barley, or rye should also be out of bounds.

If you have gluten and lactose intolerance concerns and continue with your shakes, constipation becomes inevitable.

Typically, any protein powder or premade shake marketed as gluten-free doesn’t contain these problematic grains.

However, manufacturers cannot always guarantee the absence of grains in their products, particularly if the product was not produced in a gluten-free environment.

Sugar Alcohols and Artificial Sweeteners

Meal replacements contain sugar alcohols, such as sorbitol or xylitol. It also contains artificial sweeteners, such as sucralose or acesulfame potassium. These ingredients could seriously hurt your gastrointestinal health.

In other words, they suppress the good bacteria in your gut that help with food assimilation. This leads to a range of gastric concerns, which include constipation. Make sure your meal replacement shakes do not pack in these additives.

Zero Dietary Fiber

Most people know dietary fiber is key to proper digestion. Yet, most do not make a conscious effort to consume enough amounts of fiber every day.

Since meal replacement shakes are highly unlikely to pack in any dietary fiber, they cause digestion trouble. Fortunately, increasing your fiber intake is not that difficult.

If you are paranoid over not meeting your daily fiber consumption intake target, try making your shakes yourself to add your ingredients to the shake and make the nutrient profile a bit more balanced. In other words, you may add some fresh fruits and vegetables and even nuts into the blender.

Why Dietary Fiber Is Great for Digestion

If you’re drinking meal replacement shakes daily, increasing your fiber intake is a no-brainer. You could do so by consuming a fiber-rich drink on the side or an actual meal with high fiber in conjunction with your shake.

Meal replacement shakes, as aforementioned, are known for their high protein content. When there is an excessive amount of protein in your system, your bowel area does not get the moisture it needs to facilitate the food movement.

Due to this accumulation of dry waste in your system, using the restroom becomes a lot harder, or your bathroom breaks get extended.

To prevent this situation from arising, try adding some fresh vegetables and fruit to your diet or any fiber-rich food at some point during your eating hours.

Do Not Overload on the Fiber

Despite fiber being essential for proper digestion, you could feel bloated and constipated if you go overboard with it. It’s recommended to increase your fluid intake, exercise, and make important dietary changes in such circumstances.

Generally, the bad side of fiber reveals itself if you take more than 70 grams (2.5 ounces) of fiber a day. Eating that amount is not rare. People who strictly follow a vegan, raw, or whole food diet are likely to regularly hit that threshold.

Not to mention, the digestion issues connected with fiber only get worse if there are not enough minerals, such as magnesium and selenium, in the food.

Do Not Consume Too Many Shakes in a Day

If you take meal replacement or protein shakes now and again, you would not have any digestion issues. The gastric troubles begin when you take these shakes multiple times a day. This causes a protein build-up in your system, forcing your kidneys to work harder than normal to carry out its filtration functions.

Watch this video to learn the relationship between protein consumption and your kidney health:

Kidney working overtime means frequent urination, which leaves you dehydrated. The more dehydration that happens, the more water gets absorbed from your stools. This ultimately leads to constipation.

Generally, men should consume 56 grams (1.98 ounces) of protein every day, and women must not ingest more than 46 grams (1.6 ounces) of the macronutrient.

While it’s medically safe to consume more than these recommended doses, you could be in trouble if you do not increase your fluid or water intake correspondingly.


If you’re on meal replacement shakes and face issues with your bowel movements, the protein shake may be to blame. However, do not conclude that yet.

Quite likely, several other things could have caused your constipation woes. Learning more about constipation or what causes it in the first place is imperative.

For instance, not consuming enough water during the day, not being physically active, lack of probiotics in the food, etc. are the other likely causes of constipation.

Fasting, rushing through a bowel movement, and consuming too much fiber within a short period are reasons.

If meal replacement shakes are helping you with your health goals, you need not cut them out. Just make sure you supplement or top them with sufficient fiber and drink water regularly throughout the day. Also, try to be a bit more physically active.

Our Top Recommended Meal Replacement Shakes




Beachbody Shakeology


Shakeology is our most recommended meal replacement shake because it's a nutrient dense shake that includes:

  • Protein
  • Digestive Enzymes
  • Prebiotics & Probiotics
  • Adaptogens
  • Superfoods
  • Antioxidants
  • Vitamins & Minerals
  • Omega-3 From ALA

Thus, making it perfect for weight loss, increased energy, digestive health, reduced cravings, and overall better health.

Plus, Shakeology has stood the test of time as it has been around since 2009 without compromising its whole food ingredients. Instead, Shakeology has improved their flavors in taste and potency, and has even added vegan and gluten free options.

Learn More About The Clinically Tested Shakeology Shake Here


Ample Meal

Ample Meal

Ample Meal is an interesting meal replacement as it focuses more on healthy fats. Ample Meal includes:

  • Healthy Fats with Coconut & Macadamia Nut Oil
  • Prebiotics & Probiotics
  • Antioxidants
  • Electrolytes

With Ample Meal, you can get a nice fulling 400 calorie meal with 2 scoops or do a single scoop of 200 calories if your goal is weight loss. Similar to Shakeology, it’s free of all the artificial junk that most meal replacement shakes have today.

Learn More About Ample Meal Here


Macro Meal


MacroMeal is another interesting meal replacement shake as it contains a blend of fast, medium, and slow digesting protein that delivers sustained energy. MacoMeal also includes the following core ingredients:

  • Coconut Oil Powder
  • Antioxidants
  • Probiotics
  • Multivitamins & Minerals

Although not technically a meal replacement as it’s low in carbohydrates, people have found it to be filling because of the MCT oils and slow digesting proteins.

Learn More About MacroMeal Here



Before using meal replacement shakes and exercising, I was obese and on track to having high blood pressure at the age of 25. I'm glad to say I lost 50 pounds and am living a healthier lifestyle than before. Now I like sharing what I learned when I first researched what meal replacement to drink and the best way to lose weight. Learn more about me here...

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