Crohn’s disease is when the body attacks its own intestines, leading to inflammation and symptoms like diarrhea, abdominal pain, weight loss, fever, and nausea.

Because the focus of inflammation in Crohn’s is the gut, many people believe that diet therapy can be used to treat the condition.

Many types of diet have been touted as a cure for Crohn’s. One example is the ketogenic diet. However, almost none of these diets are used by doctors to treat the condition, except the elemental diet.

Many people believe that special liquid diets (like the elemental diet) are the best treatment for Crohn’s currently available. Let’s find out what an elemental diet is and how it is used.

What is an elemental diet?

An elemental diet consists of a liquid or powder that has food nutrients already broken down.

Normally, carbohydrates, fats, and proteins are present as large molecules in your diet. These molecules need to be broken down by your intestines before the body can absorb them. Carbohydrates are broken down into glucose molecules, proteins into amino acids, and fats into fatty acids.

An elemental diet eliminates the need to break down large nutrient molecules in your diet. It contains predigested nutrients in the form of glucose, amino acids, and fatty acids as well as some vitamins and minerals. 

Most elemental diets contain more proteins and carbohydrates than fats, and we’ll see how this translates into a disadvantage of long-term elemental diet.

Elemental diet powders or liquids are usually mixed with water and consumed. No solid foods are allowed when you’re on an elemental diet. No other liquids are allowed except water and plain tea; however, hospitals differ in this recommendation.

While 95% of patients prefer to take the elemental diet via mouth, some consume it through a nasogastric tube, which is a fine tube that goes to your stomach via your nose.

How does an elemental diet work in Crohn’s disease?

There are three ways an elemental diet may help Crohn’s symptoms. First, it lets your bowel rest. The bowel doesn’t have to work hard to digest the food you eat, and this gives it plenty of time to recover from the inflammation caused by Crohn’s. 

Secondly, an elemental diet reduces the amount of undigested food molecules in your gut. While no food item has been scientifically proven to cause Crohn’s disease, many patients experience a worsening of their symptoms after eating certain food items.

This may be in part due to undigested food molecules in the gut, where bacteria feed on them to cause symptoms like bloating and nausea. Since food molecules in an elemental diet are rapidly absorbed into your bloodstream, relatively fewer molecules are left for the bacteria to feed on.

Finally, some people with Crohn’s have to undergo bowel surgery. These are the patients who don’t benefit from medications, and doctors take out the diseased segments of their bowels and reconnect the healthy ones. These patients are often put on liquid diets (like the elemental diet) to give the bowel time to recover from surgery.

Is an elemental diet effective in Crohn’s disease?

Yes, scientific literature suggests an elemental diet may help with Crohn’s symptoms. Doctors have used the diet to treat Crohn’s patients for decades.

It’s difficult to say how effective an elemental diet is in Crohn’s. According to this Cochrane review that looked at 27 studies on enteral therapy for Crohn’s, an elemental diet was not more effective than steroids in inducing a remission. However, an enteral diet was more effective than steroids in children.

The review also noted that an elemental diet was not more effective than non-elemental diets for Crohn’s. Read the next section to know more about non-elemental diets.

How is an elemental diet used in Crohn’s disease?

An elemental diet is administered under the supervision of a doctor. As a Crohn’s patient, you should never experiment with your diet without a doctor’s supervision because your gut is already compromised. And missing out on essential nutrients can lead to the development of worrisome symptoms.

There are three stages of liquid diet therapy for Crohn’s disease.

Stage one begins with you starting out a liquid diet. This can be an elemental diet or a non-elemental diet. Non-elemental diets include semi-elemental diets and polymeric diets. The main difference between the three types is the size of protein molecules — elemental diets have protein completely broken down into amino acids, semi-elemental diets have slightly larger protein molecules, and polymeric diets have even larger protein molecules.

If you start an elemental diet, you’ll take it for 2-3 weeks, while a polymeric diet would continue for around 8 weeks.

Your doctor will determine the amount of liquid diet you need, but generally you’ll need around 2.5 liters a day.

Once your symptoms regress completely, the stage 2 of diet therapy begins. This is when you start reintroducing solid foods one by one to catch the ones that trigger your symptoms. It’s just like an elimination diet. As you increase your solid food intake, your liquid diet shrinks.

Stage 3 consists of re-challenges and nutritional assessment. During stage 2, if you found certain foods to worsen your symptoms, you try them again in stage 3 to confirm that they caused your symptoms. Upon confirmation,   you avoid these items for at least 6 months.

During stage 3, you’ll also undergo a nutritional assessment. Your doctor will determine if your final diet is adequate and how it affects your symptoms. If you’ve eliminated some foods from your diet, your doctor might recommend you alternatives to make up for the lost nutrients.

What are the side-effects of an elemental diet in Crohn’s disease?

Side-effects of elemental diet include diarrhea and dysregulation of blood sugar levels. Because the diet is rich in carbs, you should be careful if you have type 2 diabetes.

Other downsides of an elemental diet are:

• Insufficient fat intake — talk to your doctor about fat supplementation
• High cost — elemental diet can cost you over $40 per day
• Difficult to follow long-term due to lack of solid foods and food choices

Finally, if you decide to follow an elemental diet, you must do it under expert supervision!

Medically Reviewed by Onikepe Adegbola, MD PhD.