Does the Keto Diet Cause Constipation?

Constipation is a common complaint for people on the keto diet. This condition is often called "keto constipation" and is the result of big shifts in eating habits. The ketogenic (keto) diet involves drastically cutting back on carbs and increasing your fat and protein intake. It's not a huge surprise if you're following the keto diet and your bowel movements become infrequent. The diet is void of fiber-rich foods that help keep you regular—resulting in keto constipation. 

Thankfully, there are ways to follow the keto diet—like drinking enough water and adding fiber-rich foods that are low-carb—to reduce constipation. Here's more about the causes of keto constipation, tips for treating and preventing it, and when to see a healthcare provider.

What Causes Keto Constipation?

People may experience keto constipation for a few reasons. The keto diet is typically low in fiber, but individuals following the diet may consume more dairy and drink less water occasionally. The combination of these factors can lead to constipation.

1. Low-Fiber Diet

Keto is lean on carbs—under 50 grams (g) a day, to be precise. Instead, it consists mainly of fats and protein. Therefore, you run the risk of under-consuming fiber-rich foods.

Consuming fiber is important. Soluble fiber works by absorbing water and encouraging the movement of food through your digestive tract. Insoluble fiber, on the other hand, acts as a bulking agent.

Reducing your fiber intake may also alter your intestinal microbiota, which is partly responsible for the breakdown of food. This lack of fiber means up to 50% of people following a keto diet will experience constipation at some point.

2. Increased Dairy

Dairy lovers may enjoy keto for its inclusion of cheeses, yogurts, and creams, which are hefty fats and protein sources. Due to its lactose (the type of sugar in milk) content, dairy is a common reason for constipation. Lactose can be hard to digest for many people and can lead to bloating, gas, nausea, and constipation.

A 2020 study evaluating the effects of high-versus-low dairy consumption on gut microbiome found that people following a high dairy diet experienced a reduction in specific butyrate bacteria, a bacteria that’s produced when you break down and digest fiber, which helps keep you regular.

3. Reduced Water Intake

Drinking plenty of water is important for all bodily functions, including staying regular. With reduced consumption of fruits and vegetables, your water intake may decrease without you realizing it.

A sudden drop in your carb intake makes dehydration and an imbalance of electrolytes all the more prevalent on a keto diet. That’s because each gram of glycogen—the stored form of sugar that’s your body’s main source of energy and is found primarily in carbs—is stored alongside 3g of water within your muscles.

How To Treat Keto Constipation

Following a keto diet is extremely strict and can be difficult to maintain. To stick with a keto diet and sidestep constipation, try the following:

1. Add More Dietary Fiber

Women should aim for around 25g of fiber daily, and men should aim for 38g daily. Luckily, there are a variety of keto-friendly, fibrous foods:

• A cup of cauliflower: 2.2g of fiber per 64g serving
• Sliced avocado: 6.7g of fiber per 100g serving
• A sprinkle of chopped almonds: 3.5g of fiber per 28.35g serving 
  

2. Exercise

Research has found that being active can help keep you regular. Aerobic exercise, in particular, can improve constipation by encouraging your intestines to contract. A brisk daily walk, light jog, or high-intensity fitness class may help regulate your bowel movements.

3. Retrain Your Bowel

Reestablishing frequent bowel movements can eradicate bouts of constipation and improve stool consistency. Retraining your bowel may be as simple as drinking sufficient fluids and establishing a regular time for a toilet break.

Stimulation, such as a fiber supplement or a suppository, may also be required. Before turning to over-the-counter (OTC) medications, speak with your healthcare provider to learn if these products are right for you.

4. Increase Your Water Intake

Sufficient hydration is essential to rid your body of waste. Your recommended water intake varies based on your sex, height, weight, and other factors, such as if you are pregnant or breastfeeding. However, most people should drink between 9 and 13 cups per day. As a rule of thumb, drink before thirst sets in and use the color of your urine as a hydration indicator. The darker it is, the more dehydrated you are. Aim to drink water with and between meals. 

5. Cut Back on Dairy

If you suspect dairy is causing your constipation, experiment with reducing or avoiding your intake. You can also consider swapping out dairy products for dairy-free alternatives. 

Other Possible Side Effects of Keto Constipation

Going on the keto diet can also result in other short-term side effects beyond keto constipation. Constipation, along with the following symptoms, is considered keto flu:

• Dizziness
• Fatigue
• Headache
• Low exercise tolerance
• Nausea and vomiting
  

How To Prevent Keto Constipation

While on the keto diet, many treatments for keto constipation can also serve as preventative measures. Other ways to prevent keto constipation include:

• Adding more high-fiber and low-carb foods permitted on keto—such as artichokes and blueberries
• Easing in by slowly introducing more fats and protein-rich foods while cutting back on the carbs if you're new to the diet
• Giving keto cycling a try to give your stomach time to adjust its digestion

Also, make sure you go to the restroom if you have to go. Holding or restricting yourself from having a bowel movement can negatively affect how your muscles work, making it harder for bowel movements to happen.

When To Contact a Healthcare Provider

It's recommended you speak to a healthcare provider before you try a new diet like keto. Speak with a healthcare provider if you're experiencing constipation but have already started on the diet. Ongoing stomach pain, bloating, gas, and even an anal fissure (a small tear in the lining of the anus) from excessive pushing are common complaints of constipation. 

Chronic constipation can also impact your mental health. A 2020 study involving 240 patients with constipation-predominant irritable bowel syndrome (IBS) found almost a third showed symptoms of depression, more prevalent among women.

Additionally, the keto diet could cause low blood pressure, kidney stones, constipation, nutrient deficiencies, and an increased risk of heart disease. Following strict diets like keto could also cause social isolation or disordered eating. Keto is not safe for those with any conditions involving their pancreas, liver, thyroid, or gallbladder.

A Quick Review

The ketogenic diet, known as the "keto diet," is a fad diet known for its potential weight loss effects. While keto may help you lose weight, it can also cause constipation, largely due to a lack of dietary fiber. You might also experience constipation because of increased dairy intake and decreased water intake. Still, you can treat and prevent keto constipation in a number of ways, like staying hydrated and eating low-carb, high-fiber foods.

It's best to talk to a healthcare provider before starting any new diet. The keto diet can be extremely restrictive and may not be for everyone.