Can a Ketogenic Diet Help Your IBS?

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You may or may not have heard some buzz about the use of a ketogenic diet for irritable bowel syndrome (IBS). A ketogenic diet is a very strict diet originally developed as a treatment for epilepsy. Because the treatment options for IBS can be somewhat limited, people with the disorder often try alternative strategies as a way to deal with symptoms and this can include making major dietary changes.

 In this overview, you will learn what a ketogenic diet is and whether or not it is a safe or helpful thing for you to consider trying for your IBS.

What Is a Ketogenic Diet?

The ketogenic diet is a very strict, very low carbohydrate, high fat, high protein diet. The diet should only be used under the supervision of a physician and with the support and guidance of a dietitian.

The diet was first designed as a treatment for epilepsy, and there is much research to show that it has the potential to reduce seizure activity for some people who have the disorder. Research on the diet was expanded into the realm of obesity and once again the research has shown that it can be an effective diet for weight loss. The use of a ketogenic diet as an effective treatment for other health problems is currently ongoing.

What Is Ketosis?

To best understand how a ketogenic diet works, you may need to review the biology of your body to get a basic understanding of a physiological state called ketosis.

Typically our bodies use carbohydrates for energy. When we fast or follow an extremely low carbohydrate diet for a few days, our bodies run out of stored glucose and are forced to turn to fat for fuel. This is accomplished by the production of something called ketone bodies. Levels of the presence of these ketones can be measured by testing your urine, blood or breath.

When ketones are present, the body is said to be in a state of ketosis and it indicates that your body is now getting its energy from fats instead of carbohydrates.

In the past, ketosis was considered to be a health state to be concerned about. However, the current view is that mild ketosis is not only not dangerous, but perhaps may have some health benefits.

What Health Problems Might Benefit from a Ketogenic Diet?

As stated above, there are two areas in which there is strong research support for the effectiveness of a ketogenic diet:

1. Epilepsy: The effectiveness of a ketogenic diet has been supported by research since 1920, with the predominant research evaluating the diet for use with children. However, there is also a substantial body of evidence that it can be effective for adults who have epilepsy. Typically the diet is used alongside anti-seizure medication. Research has shown that many people who try it the diet experience a reduction in the frequency of seizures. For a smaller percentage, the diet is so effective that they become completely seizure free.

For a smaller group, the diet is more effective than anti-seizure medications.

2. Weight loss: There is a lot of clinical research to show that ketogenic diets are effective for weight loss. But researchers don't know if weight loss occurs because of calorie restriction or if it happens as a result of carbohydrate restriction. There is research to suggest that carbohydrate restriction alone can be effective in  weight loss. Restricting carbohydrates may also improve symptoms of metabolic syndrome (pre-diabetes), type 2 diabetes, and heart disease. If you're wondering whether a high-fat diet could actually lead to weight gain, there is significant evidence that the old "fat makes you fat" thinking is now outdated.

For other health problems, research is only in preliminary stages. At this point, no firm conclusions can be drawn. The ketogenic diet is being evaluated as a treatment for the following health conditions:

  • Acne
  • Alzheimer's disease
  • Amyotrophic lateral sclerosis
  • Autism
  • Bipolar disorder
  • Brain injury
  • Cancer
  • Headaches
  • Multiple sclerosis
  • Parkinson's disease
  • Polycystic ovary syndrome
  • Sleep problems

Possible Risks of a Ketogenic Diet

Researchers believe that a ketogenic diet is a safe diet in general, but that medical supervision is warranted. There are concerns about possible kidney effects, including a higher risk for kidney stones. Other areas of concern for people who follow the diet on a long-term basis include high levels of blood cholesterol, bone fractures, and slowed growth.

Can a Ketogenic Diet Help IBS?

To date, there do not seem to be any research studies on the use of a ketogenic diet for IBS.

There is one clinical report of the use of a "very low carbohydrate diet" (VCLD) with patients who have diarrhea-predominant IBS (IBS-D). This was a very small, very brief study. Only 13 people out of an original 17 completed the study. The study protocol required participants to follow a VLCD for a period of four weeks after following a standard diet for two weeks. Most of the study participants were women and all were overweight. All meals were provided for the study participants for the duration of the six-week study. During the VCLD phase, meals were comprised of 51% fat, 45% protein, and 4% carbohydrate. As such, this diet consisted of lower fat levels and higher protein levels than is seen in a classic ketogenic diet.

The results showed that all of the participants reported adequate relief of symptoms on at least two of the weeks they were on the VLCD, and ten of them reporting adequate relief on all four weeks of the restricted diet. Adequate relief of symptoms as a measure was merely a response to a question that the participants were asked one each week. Other results included reports of a reduction in stool frequency and pain and improvement seen in stool consistency and quality of life.

These results must be viewed as preliminary due to the limited number of participants and the short duration of the study. In addition, there was no control group, so it is unknown if the positive results came from the carbohydrate restriction or from a placebo effect. Also keep in mind that the diet studied was a very low carbohydrate diet, not a ketogenic diet, so it may be hard to draw conclusions about the ketogenic diet. Lastly, it should be noted that participants were given all of their meals for a six-week period, not something that is easily replicated in real life.

What to Expect When Following a Ketogenic Diet

The ketogenic diet should ideally be taken on under the supervision of a doctor and with the support of a dietitian. The dietitian will ensure that the dieter is not only following the guidelines of the diet but that they are taking in adequate nutrition. Some treatment protocols require you to fast prior to starting the diet, but not all. The benefit of fasting is that it brings on the state of ketosis more quickly.

A dietitian can teach you what foods to eat and how to prepare them so that you are following the diet guidelines strictly. They will also provide guidance about what vitamin and mineral supplements you should take to make up for those lost by the food restriction. Typical supplements recommended to a person on a ketogenic diet include calcium, folic acid, iron and vitamin D.

If you choose to go on the diet, you will be eating more foods containing fat and fewer foods containing protein. The biggest adjustment will be the low carbohydrates intake. Because of the severe carbohydrate restriction, you may feel fatigued for the first few days of the diet. It is essential that you follow the diet guidelines strictly. Eating even one meal that doesn't adhere to the guidelines can significantly reduce any benefits that you might get from the diet.

The Bottom Line

There is currently no clinical evidence that a ketogenic diet would be helpful to a person who has IBS. The diet is quite restrictive and may be very hard to follow. For that amount of effort, you might be better served by giving the low-FODMAP diet a try - a diet that has significant clinical research to back up its effectiveness for IBS. With the low-FODMAP diet, there is also a focus on restricting carbohydrates, but only specific types of carbohydrates, labeled collectively known as FODMAPs, that have been scientifically identified as contributing to IBS symptoms.

If you are still convinced that you would like to give a ketogenic diet a try, be sure to discuss the diet with your doctor to make sure that it will not be harmful to you given your own unique medical history. You will also need to find a qualified dietitian and work closely with that person to ensure that all of your nutritional requirements are being met.


Austin G, Dalton, C, Yuming H, et al. "A Very Low-carbohydrate Diet Improves Symptoms and Quality of Life in Diarrhea-Predominant Irritable Bowel Syndrome" Clinical Gastroenterology and Hepatology 2009;7(6):706–708..

Paoli A, Rubini A, Volek JS, Grimaldi KA. "Beyond weight loss: a review of the therapeutic uses of very-low-carbohydrate (ketogenic) diets" European Journal of Clinical Nutrition 2013;67(8):789–796.

"Ketogenic Diet" Epilepsy Foundation website.

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