Keto Constipation: Causes & Remedies

May 23, 2018

Keto Constipation: Causes & Remedies

The keto diet speeds up weight loss, improves mental clarity, and increases energy levels. But it's not all sunshine and rainbows. The keto diet can also cause side effects and keto constipation is the most common one.
No one really knows why keto constipation happens. But then again, no one knows why constipation on any kind of diet happens. There are some theories, however. Some of these theories have slid scientific explanation while others are mere speculation.
We'll talk a bit about these theories here and explain how they explain keto constipation. To help you get some relief, also read our 5 tips to remedy keto constipation today.

About Constipation

A lot of people think that if they don't pass stool every day that they're constipated. This is simply not true. Medical textbooks define normal bowel frequency as anywhere between three bowel movements a day to two bowel movements a week [1].
Constipation is when stool is hard, dry, and difficult to pass in addition to being infrequent. But if you have well-formed and easy-to-pass stool occurring just once a week, then you're ok. Also, normal stool is bulky and sausage-shaped while small and lumpy stool means you're constipated. To evaluate the normalcy of your stool, take a look at the Bristol stool chart and see where you fit.
When you're constipated, you'll also feel very uncomfortable. Bloating, gas, and abdominal pain are common complaints. Some even develop hemorrhoids from chronic constipation. But there are many other complications that can happen if constipation goes untreated, so you do have reason to worry.
When you're on a keto diet, you may experience keto constipation. It's not a different type of constipation, it's simply constipation resulting from the ketogenic diet. There are several reasons why it could happen. Determining the cause will help you find the right remedy. More on that down below.  

Causes of Keto Constipation

The most common cause of keto constipation is inadequate fiber intake. But lower food intake, food allergies, and changes in gut flora can also be behind your digestive issues. Below, we discuss the most common causes of keto constipation.
Too Much or Not Enough Fiber
Increasing fiber intake is the first-in-line treatment for constipation no matter where you look or why you're constipated.
This advice comes from the assumption that you're not eating enough fiber, which is true for most adults on a typical Western diet [2]. You'll also often hear it recommended for keto because this diet tends to be low in fiber.
Fiber is an indigestible carbohydrate that gives bulk to your stool. It also stimulates bowel movements and feeds healthy bacteria in the gut. But too much can actually make your stool dry, hard, and impossible to pass. If you've been upping on the fiber on keto but don't see changes in bowel frequency, you may want to slow it down.
That's why boosting fiber is not the universal solution to constipation. In fact, some studies found that people with chronic constipation found relief once they cut down on the carbs [3]. Just like with anything in life, balance is key when it comes to fiber intake.
Another important thing that many people fail to mention with fiber intake is balancing it out with water intake. Soluble fiber absorbs water, forming a gel-like substance in your gut. If you don't drink enough water, the soluble fiber will form excessively dry, lumpy stools.
Low Food Intake
The foods you eat more of on a keto diet are high in fat and moderate in protein. This is necessary for you to enter ketosis, but they can cause keto constipation.
These foods tend to be much more filling than carbohydrates making you eat less food overall than usual.
When you eat low amounts of highly satiating foods, your digestion slows down and your bowels form less stool. This reduces the frequency of bowel movements. But a lower frequency of bowel movements isn't a problem all in itself. The problem is that the longer your stool stays in the bowels, the more water your intestines leech out of it. And with each passing day, the harder and drier stool gets.
Imbalanced Gut Flora
Eating a small number of carbs on a keto diet is important for your overall health but especially for the health of your gut. Your gut is the natural habitat of billions of friendly bacteria.
These bacteria reduce the number of harmful bacteria, ferment foods, produce short-chain fatty acids, make vitamins and enzymes, and maintain immunity [4].
Health-promoting gut bacteria feed largely on soluble fiber. Without enough soluble fiber in your diet, their numbers drop, and you experience diarrhea, keto constipation, and nutrient malabsorption. Higher fat intake on a keto diet can also boost the numbers of fat-fermenting bacteria and lead to dysbiosis [5], which is a fancy word to microbe imbalance.
There are luckily ways to prevent gut dysbiosis even while on a ketogenic diet. When dysbiosis is the culprit behind your keto constipation, your stool will become greasy, float, and smell really bad. The stool may also be pale due to fat malabsorption.
Other Possible Causes
Milk protein allergies, certain medications (codeine and antidepressants), inactivity, low thyroid hormones, and premenstrual syndrome (PMS) can all cause constipation and contribute to keto constipation.
. If you notice constipation worsens or gets better from time to time, it could be due to changes you made in any of these risk factors.

Treating Keto Constipation

Treating keto constipation is easy once you understand the causes. Here are some simple tips for you to follow.
#1 Balance out your fiber intake
If your stool is hard to pass and your bowel movements few and far between, make changes to your fiber intake. Current guidelines recommend eating 25 to 30 grams of fiber per day, with at least some of that fiber being the soluble kind.
You can get enough fiber from a range of keto-approved plant foods like coconut flour, almonds, celery sticks, peanut butter, and flaxseed. You can also take it as a supplement. Psyllium husk is the most popular and effective fiber supplement out there.
Do reduce your fiber intake if you're eating enough now but are constipated and see if this makes a difference. Also, do drink enough water. Keto dieters should drink 11 to 15 cups of water a day depending on their size.
#2 Take probiotics
If your fiber intake is optimal, chances are you're already giving your gut bacteria enough food to thrive. But if your stools are greasy and foul-smelling, then you may need some help from probiotics.
Probiotics are live bacteria and yeast you can get from food or supplements. Yogurt, kefir, sauerkraut, and miso are all good sources of probiotics. Make sure to take them with soluble fiber to help them survive in the digestive tract.
One large systematic review explains that most studies speak in favor of probiotics [6]. Evidence shows that probiotics from food alter and restore gut flora. The same review also states that probiotics improve bowel movements.
The most common probiotic strains are Lactobacillus and Bifidobacterium. Some strains also occur in symbiosis with fungi like in kefir and sourdough.
#3 Eat more and drink more
To boost stool bulk, you want to eat more food and drink more liquids throughout the day. The keto diet has an appetite-suppressing effect, which is great for weight loss. However, it's often a bad thing for bowel frequency.
To make sure you're eating enough, it's a good idea to plan your meals. Add ingredients from different food groups and combine low-calorie with caloric foods. Also add plenty of fiber-rich foods like avocados, almonds, and coconut flour.
Drink different liquids throughout the day to get enough fluids. Water, tea, smoothies, and soups all contribute to your daily hydration levels. It's best to take liquids together with meals to improve digestion.
#4 Get Moving
Chronic constipation in adults is often linked to inactivity [7]. Being inactive reduces blood flow to your digestive tract which slows down digestion. Physical activity also stimulates the digestive tract and tones abdominal muscles.
People who are bedridden also often experience constipation. But the majority of people with this problem simply don't have the time to dedicate to exercising. Nevertheless, exercising and strenuous activity is essential for normal bowel movements and overall health.
On a keto diet, exercising also helps you get into ketosis quicker and it also improves energy levels. Current guidelines recommend 150 minutes of moderate aerobic activity every week for optimal health [8].
#5 Eliminate food triggers
Many keto dieters find that excluding or limiting dairy helps with keto constipation. Even research shows a strong link between chronic constipation and cow's milk allergies [9, 10]. Constipation due to milk allergies happens because allergies cause inflammation inside the intestines preventing normal functioning.
Other common allergens include eggs, peanuts, soy, seafood, and wheat. Note that many of these foods are high in protein. Food allergy is by definition an adverse reaction to food proteins. Try excluding different protein foods from your diet and see if it makes any difference. You can also always ask your doctor to check for food allergies.


Keto constipation is a common problem. Luckily, it's easy to avoid and remedy once you get to the root cause. From too much or too little fiber to lack of physical activity and food allergies, there are many causes of keto constipation. Finding out which one is the culprit in your particular case is a bit tricky, though.
Try following our 5 easy tips and tricks and see what works for you. The keto diet being restrictive in carbs means that inadequate fiber intake is the likely cause of your keto constipation. Boosting your fiber intake through low-carb keto plant foods or supplements. Drinking water and staying active also helps.
If you've tried everything and nothing seems to help, you may need to ask your doctor for help. Constipation lasting longer than a week likely won't resolve on its own. Besides that, it puts you at risk of complications.