Keto Constipation: How Long Till Relief?

The keto diet is a very high-fat, low-carb, and moderate-protein eating pattern that induces a phenomenon called ketosis. While the keto diet may help burn fat, it can also have side effects, such as constipation. Constipation is a common issue for people on the keto diet due to the drastic reduction in carbohydrate intake, which can lead to a decrease in fiber intake. This transition period can last a few days to a few weeks, and in some cases, even longer. During this time, people may experience infrequent bowel movements, typically defined as fewer than three per week, and hard, dry, or lumpy stools. To treat and prevent constipation, it is recommended to increase water intake, consume more dietary fiber, and ensure adequate physical activity.

Dietary changes

Increase Your Fibre Intake

A sudden change in your fibre intake can cause constipation. The keto diet is low-carb, so you may not be getting enough fibre from grains. It's best to slowly change the amount of fibre in your diet rather than making dramatic changes. Aim for 25g of fibre daily for women and 38g for men. Good sources of fibre include:

• Non-starchy vegetables (e.g. greens, broccoli, cauliflower, asparagus)
• Berries (in limited amounts)
• Avocados
• Nuts and seeds

Stay Hydrated

The keto diet can lead to dehydration, which can cause constipation. Drink plenty of water throughout the day, especially if you are exercising or spending time in the heat. Aim for 9-13 cups of water per day. Your urine should be light-coloured; if it's dark, you need to drink more water.

Avoid Dairy

Dairy products are allowed on the keto diet, but they can be hard to digest and lead to constipation. Try going dairy-free for a few weeks and see if your digestion improves.

Cut Back on Inflammatory Foods

The keto diet is generally anti-inflammatory, but some keto-friendly foods can be inflammatory for some people. These include:

• Dairy
• Nuts (also high in fibre)
• Eggs

Increase Your Electrolyte Intake

Keep your electrolytes up to ensure proper hydration and support bowel function. The primary electrolytes are sodium, potassium, and magnesium. You can increase your electrolyte intake by:

• Consuming mineral water
• Taking magnesium supplements (e.g. magnesium citrate, magnesium glycinate)
• Increasing your salt intake (12 grams per day when transitioning into ketosis, then reducing to 5 grams per day)

Eat More Fat

The keto diet is a high-fat diet, so make sure you're eating enough fat. Fat triggers the release of bile, which aids digestion and acts as a natural laxative. Choose healthy fats like:

• Coconut oil
• Butter
• Animal fat (lard, tallow, suet)
• Olive oil
• Avocado oil

Lack of fibre

Constipation is a common issue for people on the keto diet, and it is often caused by a lack of fibre-rich foods. The keto diet is typically low in fibre, and individuals following the diet may occasionally consume more dairy and drink less water. The combination of these factors can lead to constipation.

The keto diet consists of under 50 grams of carbohydrates per day, mainly fats and proteins. This means that you may not be consuming enough fibre-rich foods. Soluble fibre absorbs water and encourages food to move through your digestive tract, while insoluble fibre acts as a bulking agent.

Reducing your fibre intake may also alter your intestinal microbiota, which is partly responsible for breaking down food. A lack of fibre means that up to 50% of people following a keto diet will experience constipation at some point.

How to Address Lack of Fibre

• Add More Dietary Fibre: Women should aim for around 25 grams of fibre daily, and men should aim for 38 grams. There are various keto-friendly, fibrous foods, including non-starchy vegetables, limited amounts of berries, avocados, and nuts.
• 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.
• Retrain Your Bowel: Reestablishing frequent bowel movements can help eradicate constipation and improve stool consistency. Retraining your bowel may involve drinking enough fluids and establishing a regular time for a toilet break.
• Increase Your Water Intake: Staying hydrated is essential for regular bowel movements. Most people should drink between 9 and 13 cups of water per day. Aim to drink water with and between meals, and use the colour of your urine as a hydration indicator.
• Add More Fibre-Rich, Low-Carb Foods: Include more high-fibre and low-carb foods permitted on keto, such as artichokes, blueberries, and non-starchy vegetables like greens, broccoli, asparagus, and cauliflower.

Dairy intolerance

If you suspect dairy is causing your constipation, try reducing or eliminating your intake for a few weeks. You can also try swapping dairy products for dairy-free alternatives.

The keto diet can include full-fat dairy, and many people end up consuming more dairy than they usually would. However, the keto diet is already low in fibre, and dairy can compound this issue. Dairy is also a common cause of constipation due to its lactose content, which can be challenging to digest and lead to bloating, gas, nausea, and constipation.

A 2020 study found that people on a high-dairy diet experienced a reduction in specific butyrate bacteria, which is produced when breaking down and digesting fibre. This bacteria helps keep you regular.

If you are lactose intolerant, you may find that a keto diet exacerbates this issue, as you are more likely to consume larger amounts of dairy.

• Try going dairy-free for a few weeks and monitor your digestion.
• Experiment with reducing or avoiding dairy products and opt for dairy-free alternatives.
• Increase your water intake to stay hydrated and aid digestion.
• Consume more high-fibre, low-carb foods, such as cauliflower, cabbage, and berries.
• Exercise regularly to promote bowel movements and improve digestion.
• Consider taking a fibre supplement to increase your fibre intake and promote regularity.

Remember to speak with a healthcare professional before making any significant dietary changes or if you are experiencing persistent constipation.

Dehydration

When you start the keto diet, your body transitions from burning glucose (from carbs) for energy to burning fat. This transition involves a process called ketosis, where the body taps into its glycogen stores. Glycogen is a larger, more complex form of glucose that the body metabolises after it burns through all its readily available glucose. Each gram of glycogen is stored with at least 3 grams of water, so when you deplete those glycogen stores, you lose a lot of fluid. This can lead to dehydration, especially if you don't adequately increase your water intake.

To prevent dehydration and the potential for constipation when starting the keto diet, it's essential to increase your water intake. Aim for 9-13 cups of water per day, and drink before you feel thirsty. You can also check your urine colour; if it's a light lemonade colour, you're adequately hydrated.

In addition to increasing your water intake, you can also try the following to prevent dehydration and constipation:

• Increase your salt intake, as sodium helps the body retain water.
• Supplement with electrolytes, especially magnesium, as they make water more hydrating.
• Drink caffeinated beverages, as they can act as mild natural laxatives.
• Exercise regularly, as physical activity promotes bowel movements.

By staying hydrated and following these additional tips, you can help prevent constipation when starting the keto diet.

Electrolyte imbalance

When you start a keto diet, your body will begin to process electrolytes differently. This is because when insulin levels are low, the kidneys excrete more sodium. As there is a delicate balance between sodium and other electrolytes in the body, the loss of sodium may disrupt levels of other electrolytes as well. This can lead to symptoms of the "keto flu", such as constipation.

Sodium

Sodium is the most important electrolyte to replenish. Most people on a low-carb diet will likely feel best with 3–7 grams of sodium (7–17 grams of salt, or about 1-3 teaspoons) per day. You can add a teaspoon of salt to a liter of water and drink it over the course of the day. Another strategy is to drink broth or bouillon, which contains about 1 gram of sodium per cup.

Potassium

Potassium is the second most important electrolyte to replenish. To get more potassium into your diet, you could take potassium supplements. Or, why not try adding an avocado or a couple of servings of other low-carb-friendly high-potassium foods to your diet on a daily basis?

Avocado – 1,000 mg per large avocado (200 grams)

Swiss chard, cooked – 950 mg per cup (175 grams)

Spinach, cooked – 840 mg per cup (180 grams)

Mushrooms, cooked – 550 mg per cup (150 grams)

Brussels sprouts – 500 mg per cup (160 grams)

Broccoli, cooked – 460 mg per cup (160 grams)

Salmon – 430–500 mg per 4 ounces (114 grams)

Meat – 400–500 mg per 4 ounces (114 grams)

Flounder – 400 mg per 4 ounces (114 grams)

Artichoke – 345 mg per medium artichoke (121 grams)

Hemp seeds – 335 mg per ounce (30 grams)

Almonds – 200 mg per ounce (30 grams)

Magnesium

Magnesium is essential for over 300 processes in the body. Symptoms of magnesium deficiency may include muscle twitching or cramping at night or after exercising. Although muscle cramps can also occur with inadequate potassium, sodium, or fluid intake, getting too little magnesium can be a common cause.

Hemp seeds – 195 mg per ounce (30 grams)

Swiss chard, cooked – 150 mg per cup (175 grams)

Pumpkin seeds, dried – 150 mg per ounce (30 grams)

Mackerel – 105 mg per 4 ounces (114 grams)

Chia seeds – 95 mg per ounce (30 grams)

Dark chocolate (70–85% cacao) – 70–90 mg per ounce (30 grams)

Almonds – 75 mg per ounce (30 grams)

Spinach, cooked – 75 mg per cup (180 grams)

Pine nuts – 70 mg per ounce (30 grams)

Avocado – 60 mg per large avocado (200 grams)

Artichoke – 50 mg per medium artichoke (120 grams)

Taking up to 400 mg of magnesium per day in supplement form is safe for most people with healthy kidneys. Some forms of magnesium can cause digestive issues, however, especially when taken alone. For this reason, it’s best to take a magnesium supplement with a meal.

Frequently asked questions