Keto is a very reliable weight loss diet. Going keto involves eating less than 50 grams of carbs per day and filling up on lots of fat and moderate amounts of protein. This macro ratio produces rapid weight loss and, with no carbs to use for energy, your body turns into a certified fat-burning champion.
Unfortunately, initially at least, the keto diet can cause a few side effects, collectively called the keto flu. These symptoms include fatigue, headaches, and stomach upsets. And yes, that includes keto diarrhea.
While this is not a pleasant subject to think about (or write about!), it’s enough of a problem that it needs to be addressed. The good news is that you don’t have to ignore or live with this symptom; there are several things you can do to cure or even avoid it in the first place.
It’s also important to know that keto diarrhea, like the other symptoms of keto flu, usually disappear all on their own when you complete the initial keto induction phase. Once you transition from using carbs for fuel to burning fat and ketones, your keto flu symptoms will quickly become a thing of the past.
What is diarrhea?
As a rule, your bowel movements should be regular, predictable, and firm. This is a good indicator that your digestive system is working correctly. With diarrhea, bowel movements are very watery and loose. You may also find that the urge to go to the bathroom is much less predictable. The occasional loose bowel movement is entirely normal, but if you find yourself rushing to the bathroom several times a day for a couple of days or more in a row, you have diarrhea and should take steps to fix the problem.
Diarrhea can have a big impact on the quality of your life. You’ll lack confidence in your ability to control your bowels and may be reticent to stray too far from a bathroom. Diarrhea may also be accompanied by cramps or pain in the abdomen. It can also cause dehydration. Dehydration is a common enough problem with keto so adding diarrhea into the mix could make matters worse. Dehydration is particularly worrisome for older people and those who live in hot climates.
Not all keto dieters get diarrhea. In fact, it’s a relatively rare keto side effect. But, because it’s such an unpleasant problem, it’s worth making sure that, if you do experience keto diarrhea, you can sort it out as soon as possible.
Causes of keto diarrhea
One of the reasons that the keto diet is so effective is that it causes some significant changes within your body. Unlike most diets that merely limit the amount of food you eat, keto makes your body function differently. However, as profound as these changes are, they do not happen overnight.
Initially, when you cut down on carbs, your body has to rely on its existing carbohydrate stores. These can last several days to a week or two. As these stores are depleted, your body gradually makes the transition to using fat and ketones for energy. During this period, your body is caught between a rock and a hard place – it’s running low on carbs but is not yet in full ketosis. This creates a degree of upheaval and causes all those keto flu symptoms.
Introducing or eliminating certain foods and food groups can have a big impact on your gastrointestinal system and health. Unlike most diets, where you just eat less of the foods you usually consume, with keto you will find yourself eating foods that may be unusual and not eating foods you are used to eating.
This is not unlike that other common cause of stomach upset – exotic food. Eating on vacation is a common trigger for diarrhea. It’s not that the food you eat is in any way bad or unhealthy; it’s just that it’s different. Your body may not react well to these keto diet food changes, and the resulting diarrhea is the outward sign.
In addition to what is best described as food sensitivities, diarrhea on the keto diet can also be caused by changes in your gut bacteria. Don’t panic, you are supposed to have bacteria in your gut, and it’s actually a good thing! These bacteria play a critical role in digesting the food you eat and maintaining your immune system. However, if your gut bacteria are disrupted, as can happen when you change your diet, diarrhea is often the result.
A significant increase in fat intake is also thought to be another cause of keto diet diarrhea. Most people, before going keto, follow a low to moderate fat diet. However, when you go low-carb, your fat intake will suddenly jump up to where 70-80% of your calorie intake comes from fat.
Fat takes a lot of work to break down and digest, and some people are better at it than others. Undigested fat enters your small intestines and colon and draws more water into your GI tract to help it move through your digestive system. This causes dreaded diarrhea. If this is the cause of your diarrheal symptoms, you may notice an oily sheen floating on the water in your toilet. The good news is that, as your body gets used to digesting fat, this symptom should soon disappear. There are also a few hacks that will improve your ability to digest fat – revealed later!
The final common culprit of keto diarrhea is artificial sweeteners and, in particular, sugar alcohols. Many keto dieters use non-sugar sweeteners so that they don’t have to live off anything other than meat, vegetables, and nuts. There are lots of keto-friendly-foods available where sugar and carbs have been replaced with artificial sweeteners.
Because artificial sweeteners and sugar alcohols are not digested and absorbed in the gut, they often reach the large intestine and, on arrival have a laxative effect. That’s why, if you read the small print on things like sugar-free mints and gum, you’ll see a warning stating that overconsumption can lead to gastric distress.
How long does keto diarrhea usually last
If you suffer from keto diarrhea at all, it usually only lasts as long as it takes your body to enter full ketosis. This can take a few days and up to a week or two depending on several factors. To get through keto induction as fast as possible and reduce the duration of keto diarrhea, make sure you take the following steps:
1. Cut your carbs and keep them low – if you consume more than 50 grams of carbs per day, you run the risk of delaying ketosis and prolonging your diarrheal symptoms. Use a food tracking app to make sure you aren’t eating more carbs than you should. For best results, keep your carb intake to between 20-30 grams per day.
2. Do some exercise – speed up your descent into ketosis with exercise. Exercise depletes your muscle glycogen stores. The sooner you use those stores, the sooner you’ll get into ketosis.
3. Eat enough fat – low fat keto diets are not usually very effective. Eating a lot of fat may be a foreign concept to you, but it’s what you need to do to burn fat and lose weight. Eating more fat will get you into ketosis faster than eating too little. Use your food tracking app to make sure that 70-80% of your calories come from fat.
4. Try fasting – fasting will get you into ketosis faster than keto alone. When you skip meals, your body is much more likely to use stored carbs for energy. Fasted exercise, i.e., working out on an empty stomach, will also speed up your descent into ketosis.
5. Use some keto diet supplements – there are several keto supplements that will help you get into ketosis faster. Good choices include:
- Alpha lipoic acid (ALA)
- Conjugated linoleic acid (CLA)
- Exogenous ketones
To clarify, the sooner you get into ketosis, the sooner your keto diarrhea will stop. However, if you are in ketosis and you still have diarrhea, it could be that you are struggling to digest all the fat you are eating or may be intolerant to one of the foods you are eating. Don’t give up yet – there are still solutions available.
How to prevent or cure keto diarrhea
Struggling with keto diarrhea or just want to avoid it in the first place? Here are some practical tips that should help!
1. Go easy on sugar-free foods
Sugar-free foods may seem like a godsend for keto dieters, but they may be doing more harm than good. Remember, even though calorie and carb-free sugar substitutes won’t affect ketosis, they can cause gastrointestinal distress, especially when consumed in large amounts.
A lot of keto diets make the mistake of trying to replicate their pre-keto diet with sugar-free foods and end up consuming way more artificial sweeteners and sugar alcohols than they should. While you should have no problem with the occasional can of diet soda and a few sticks of sugar-free gum, if you are consuming lots of these products, you are much more likely to suffer from diarrhea.
Eating fewer products that contain artificial sweeteners and sugar alcohols may help relieve or prevent keto diarrhea.
2. Don’t overdo the protein
Remember, keto is a high fat, moderate protein, and very low carb diet. That’s how it works! However, some dieters are tempted to eat more than the recommended 20-30% protein, and this can lead to diarrhea. To digest and utilize protein effectively, your body needs an abundance of fat. Eating too much protein means you’ll invariably end up eating less fat, and this may increase your risk of diarrhea.
3. Eat the right fats
While keto is undeniably a high-fat diet, it’s important to remember that not all fats are created equal. There are several different types of fats, and your body digests and tolerates some better than others.
Saturated fats are very stable and inert. Your body likes to use saturated fats for energy and energy storage. Contrary to popular belief, eating saturated fat won’t clog your arteries or give you a heart attack! In fact, saturated fat has anti-microbial properties that mean it’s actually good for your intestinal health.
Monounsaturated fats are more reactive which means your body can use things like olive oil and avocado oil for a range of critical physiological functions. Monounsaturated fats are considered to be very heart-healthy.
Polyunsaturated fats are considered to be the healthiest of all the fats. Highly reactive, your body likes to use fats like soybean, corn, safflower, or sunflower oils for a range of chemical and cellular reactions.
While it would appear that you should consume lots of polyunsaturated fat, moderate amounts of monounsaturated fat, and limited amounts of saturated fats, the reverse is actually true. To lose weight and avoid diarrhea, the majority of your fat intake needs to come from monounsaturated and saturated sources such as olive oil, high oleic versions of safflower and sunflower oil, lard, butter, cream, and high-fat cheese.
Two facts that are especially useful on the keto diet are MCT (medium chain triglyceride) oil and MCT-rich coconut oil. Both are easy to digest and consuming them should help prevent and alleviate diarrhea.
4. Don’t go fiber-crazy
Fiber is an important food substance on the keto diet. Eating less bread, rice, pasta, and potatoes may mean you inadvertently eat less fiber than usual, and this could lead to constipation. Aware of this potential problem, a lot of people go overboard on things like laxatives and supplemental sources of fiber such as psyllium husks or powder.
Unfortunately, overusing these supplements can tip the balance too far the other way, leading to diarrhea.
If you do suffer from constipation, eat more fibrous veggies, drink more water, and get some exercise to relieve the problem gently. MCT oil and coconut oil may also help. However, unless the problem persists, avoid “heavy hitters” like laxatives and other bowel boosters as they could turn your constipation into diarrhea.
5. Watch out for common food allergens
Going keto will probably mean you have to start eating foods that, until now, you didn’t eat very often. This could be a cause of diarrhea. Eating more eggs, nuts, full-fat dairy, or other common keto foods could be your intestinal nemesis. Eliminate common food allergens one by one to determine if one of them is triggering diarrhea.
6. Balance your electrolytes
During your transition into ketosis, your body loses a lot of water. As glycogen is used for energy, your muscles and liver release a lot of water, and that water must be excreted. All that extra peeing means your body also expels minerals called electrolytes. If your electrolytes become unbalanced, you may suffer from diarrhea. The electrolytes are:
Rebalance your electrolytes by eating plenty of low-carb non-starchy vegetables, using an electrolyte supplement, or making your own homemade ketoade. Here is a keto electrolyte drink recipe to try. It makes six servings, and each one contains only 1.7 grams of carbs and six calories.
- 5 cups water or herbal tea of choice. You can also use coconut water
- ½ cup lemon or lime juice
- ½ teaspoon potassium chloride (or you can use lite salt or cream of tartar)
- ¼ teaspoon pink Himalayan sea salt
- 2 tablespoons Natural Calm magnesium supplement
- Calorie/sugar-free sweetener to taste
Drink one serving per day with food.
7. Use digestive enzymes
If your diarrhea is the result of problems digesting fat, a supplement called a digestive enzyme may help. The enzyme that digests fat is called lipase. In addition, you may benefit from increasing bile acid production. Bile acid helps emulsify fats for easier digestion. Increase hydrochloric acid (HCL), which is the trigger for the liver to produce bile, by consuming one tablespoon of apple cider vinegar, three times per day.
8. Eat more probiotic and fermented foods
Gut bacteria imbalances can cause diarrhea. Repopulate and boost your healthy intestinal flora and fauna with probiotics and fermented foods. Good choices include:
- Probiotic supplements
Contrary to the popular kids’ rhyme, there is nothing funny about runny diarrhea. While a mild or occasional attack is common and nothing to worry about, a prolonged attack could leave you dehydrated and questioning whether you should even leave the confines of your bathroom. Diarrhea at night can also disrupt your sleep.
Not all keto dieters suffer from diarrhea, but it happens often enough that at least a few people will have loose bowel horror stories to share. The good news is that keto diarrhea is neither inevitable nor untreatable. In fact, in a lot of cases, you can fix or even avoid it quickly and easily.
However, if your diarrhea is severe, doesn’t respond to the interventions outlined in this article, or lasts more than a week, you should discuss your symptoms with your doctor as it could be a sign of something that would benefit from medical treatment.