Crohn’s Disease Diet

Updated 06/14/2021
Category: Diet

Please refer to the essay on Crohn’s Disease for more detailed information on this disorder. Dietary treatment for Crohn’s Disease must start with a solid partnership with your physician.

This information will supplement your knowledge of dietary factors that may beneficially influence your disease.  It is for the Crohn’s patient who is reasonably stable.  For those with very active disease with severe symptoms or if there is fixed narrowing in the bowel, this information may not be appropriate.  Consultation with the physician is advised.

It would seem reasonable to assume that the foods and liquids we eat or drink would be important.  Yet, it has been difficult to uncover whether certain foods are beneficial or that some are downright harmful for Crohn’s patients.  So what do we now know and what can we say about the specific foods which a CD person should eat or should avoid?  A large medical study has been published in the American Journal of Gastroenterology in 2,011 which analyzed what people ate before they developed CD (1).  They reviewed over 1,000 medical articles and found 19 that addressed this problem in a satisfactory manner.  Their findings were simply stunning.

There was an increased risk of getting Crohn’s if a person ate:

•  a high protein and/or meat diet
•  a high fat diet, meaning saturated fats but also polyunsaturated vegetable and omega-6 fats
•  a low fiber diet

Some of the reports studied looked at all animal protein that was consumed – meat, poultry, fish, and dairy products.  Others looked just at meat.  The consensus seemed to be that Crohn’s patients should not go overboard on animal protein, especially meat.  In the past, it was felt that there was no limit to the amount of animal protein eaten.  The data now seems to show that a high protein diet, meaning 75-100 grams or more of protein a day may not be helpful and may actually be harmful.  Fifty grams of animal protein a day might be enough, about the size of a deck of cards.

Saturated fats are those found in well-marbled meat, bacon, all processed meat, whole milk, chicken skin, butter and lard.  But it is the information on the unsaturated fats that was important.  These are the fats found in fatty fish, nuts and vegetable oils.  We know that these fats and oils offer protection against coronary heart disease but to find that they may actually increase the risk of CD is disturbing.  Nevertheless, this is what this careful study showed.  So, high fat foods, including even vegetable oils need to be used in lower amounts.

Finally, the study indicated that people who were destined to get CD had a low intake of plant fiber, meaning vegetables and fruit.  People who ate over 22 grams of fiber a day and especially those who had a high fruit intake had a significantly lower risk of getting CD.

It needs to be stressed that this careful review study looked at what people ate before they developed CD.  We just do not have good data on what is best after CD is diagnosed.  However, it does make sense to give this type of diet a trial as there is nothing in it that is detrimental and it just might be very beneficial.

Animal Protein

Amino acids are the building blocks of protein in your body.   No matter what protein you eat, it is broken down in your gut into amino acids, which are then absorbed by your upper intestine.  Then your body will build the specific proteins it needs to remain healthy.  Animal protein is a complete protein, meaning it has all the amino acids the body needs.  A specific vegetable protein, on the other hand, is an incomplete protein, meaning that each vegetable lacks a few of these essential amino acids.  However, eating a variety of vegetables will correct this as some vegetables will make up for those amino acids missing in others.  Fifty grams of animal protein a day will provide all the amino acids your body needs.  A piece of meat or chicken about the size of a deck of cards will usually suffice.  You need to read labels on milk, cheese and other foods derived from animals and to become educated on protein in all foods you eat.  The amino acids derived from vegetables and fruits are just as good as those derived from animals.

Fiber

Every vegetable, grain or fruit has fiber in it.  It is what gives a plant its specific shape.  Fiber generally comes in two types, insoluble and soluble.  Insoluble fiber does not dissolve in water but rather moves through the colon unchanged, retaining water and providing bulk and regularity. Wheat fiber is an example of insoluble fiber.  Soluble fiber, on the other hand, does dissolve in water.  Oats are very high in soluble fiber.  Soluble fiber is the primary nutrient for the huge number of good bacteria that reside in the gut.  The very best of these soluble fibers are called prebiotics.  These prebiotic fibers have been shown to be fermented by the good bacteria in the bowel and, in so doing, produce multiple health benefits.  Fermentation means that the soluble fiber is used by the good colon bacteria as a fuel and allows them to grow and multiply.

National authorities and diet experts recommend the following daily intake of fiber derived from plants.  The numbers are for the average man or woman and will obviously depend on body size and weight.  Men:  30 grams or more and Women:  25 grams or more

Counting fiber should not be difficult.  Every packaged food will have grams of fiber listed on the label.  For fresh vegetables and fruits, you can go to Fiber Content of Foods to get a fiber count on virtually any foods.

People with Crohn’s Disease may have to be careful when they increase fiber intake.  A Crohn’s patient should increase fiber gradually, so that the intestine becomes accustomed to it.  Cruciferous vegetables (cabbage, broccoli and Brussels sprouts), beans, spicy foods and any drinks that contain caffeine may have to be used sparingly until their effect in the gut is known.  Harmless temporary bloating or gas may otherwise occur.

Gut Bacteria

The lower intestine, especially the colon, is home to huge numbers of bacteria of over 1,000 different species.  Newer research techniques have expanded our knowledge of these bacteria and how they act in the gut.  For the most part, they are very beneficial and provide many health benefits for us.  This is particularly true when they receive the proper fiber nourishment from the foods we eat.  For Crohn’s patients, some of these colon bacteria may be enemies.  Most Crohn’s patients have an abnormal makeup of the gut bacteria whereby there is a predominance of these bad bacteria.  It is these unwanted bacteria that invade the wall of the gut and begin the inflammatory Crohn’s process.  No one can get rid of these bad bacteria entirely.  But we can encourage the good bacteria to thrive thereby reducing the importance of these bad bacteria. This is done by increasing fiber ingestion.  When the good bacteria thrive, the bad bacteria are suppressed.  In addition, certain substances are produced by these good bacteria that actually strengthen the bowel wall.  These are called short chain fatty acids (SCFA).  These are the nutrients for the cells that line the colon.  They also acidify the colon, which is a very good thing and helps suppress the growth of some bad colon bacteria.  It makes sense to encourage the production of as much of these SCFAs as possible.

Prebiotics

Prebiotic plant fibers are the very best soluble fibers.  They are present in many vegetables and a few fruits.  These prebiotic plant fibers promote the growth of the best gut bacteria.  When these bacteria thrive, many beneficial outcomes occur, including better immunity, increased calcium and magnesium absorption, a healthier bowel wall (less leaky gut), and others.  Oligofructose and inulin are the names of the naturally growing soluble fibers that have been shown by medical research to have the best effects.  These prebiotic fibers are particularly rich in wheat, rye, leeks, asparagus, chicory and Jerusalem artichoke root, bananas, onions, garlic, yams, agave and others.  A prebiotic supplement is also available, Prebiotin.

Fruits

A surprising research finding is that significant fruit ingestion appears to have a protective effect for Crohn’s patients.  Fruits have many soluble and insoluble fibers in them, so fruit can be recommended in almost any quantity.  Some people with Crohn’s feel that raw fruit juices are a problem, so you need to be careful when drinking these.

Dairy Products

Lactose is the sugar in milk.  Many people are intolerant of lactose and they may have some of the same symptoms that a Crohn’s person has, such as abdominal cramps, gas and diarrhea.  In addition, a person may have both CD and lactose intolerance.  So be careful of dairy products or use lactose free foods.  A simple test for lactose intolerance can be done at home.  On a free day, drink 16 oz of fat free milk in the morning as your only food.  If you do not have the symptoms of gas, bloating or diarrhea within 5-6 hours, then it is unlikely that you are lactose intolerant.

Liquids and Fluids

Adequate fluid intake is particularly important for CD patients.  Diarrhea may be a prominent symptom so that at least 70 oz of fluid per day can be recommended for a 140 lb person.  Since dehydration may be a problem, adequate salt or sodium can be used.  However, excessive salt may push up the blood pressure.

Vitamins

Vitamin intake is particularly important for CD patients. This needs to be discussed with your physician.

•  Multiple vitamin with minerals – For most CD patients, a daily multiple vitamin can be
  recommended.
•  Folic acid or folate – Be sure this is present in your multivitamin.  Fruit is a rich source of folate.
•  Vitamin B12 – Some Crohn’s patients do not absorb enough B12 and they may need monthly
  injections.  The physician will want to check the blood level periodically.
•  Vitamin D – This vitamin is important for bone health.  Crohn’s Disease patients may be
  particularly susceptible to the early development of weak bones or osteoporosis.  Vitamin D
  deficiency in the general population has now been found to be far more common than was
  previously thought.  Some experts are now recommending at least 800 IU and even 1200 IU
  per day, along with at least 1,200 mg of calcium in the form of milk and/or supplements such as
  calcium carbonate.  Check with your physician.

Minerals

• Calcium – Most adults need 1,200 mg of calcium each day.  Calcium can best be obtained from
  milk, other dairy products, shellfish, and, if needed, calcium supplements.  If you take steroids
  such as prednisone, it is even more important that you get enough vitamin D and calcium, as
  steroids are known to weaken bones.  A prebiotic dietary fiber supplement can also help to
  increase calcium absorption.
• Iron – Many Crohn’s patients have a low iron level, which can lead to anemia.  Your physician
  will want to check the iron blood level periodically.
• Selenium – Selenium appears to act like an antioxidant in the body.  Some medical studies show
  that selenium may be low in Crohn’s Disease patients and that they do better when they take
  a selenium supplement.  200 mg per day is recommended.  Check with your physician.

Prepared, Packaged and Bottled Foods

We know that the rising incidence of CD parallels the improvement in the Western lifestyle of living.  Diet, as outlined above with large quantities of cheap meat and fats, is one factor that is likely contributing to CD.  The second factor that may be important is that so many of the foods we eat and which are so readily available are those foods that are packaged, bottled or prepared in a food factory far away from where you purchase them.  Food manufacturers add a very wide range of chemical additives to their foods to enhance taste, smell or appearance, to provide good mouth feel and especially to ensure long shelf life.  Each of these substances by itself has long ago been approved by the federal FDA.  However, many of these substances have not had rigorous research on their long term safety, particularly when so many and/or so much of them are ingested.  There has been no or little research on what happens when they come together in the intestine.  This could be especially important to the Crohn’s patient whose intestines are exposed to so many of these food additives.  A possible very important group of additives are the food emulsifiers.

Emulsifiers

An emulsifier is a chemical that is added to packaged, bottled or prepared foods in order to provide a benefit.  For instance, an emulsifier is added to almost all bottled salad dressings.  It acts like an emulsion and allows the mixing of water and oil within the bottle.  Emulsifiers are often added to ice cream in order to enhance taste and mouth feel. In other instances the emulsifier may allow prolonged shelf life.  Finally, emulsifiers have no calories; they provide the mouth feel of fats and so they are used extensively in low calorie packaged foods.  The FDA has allowed food manufacturers to use these chemicals as they wish in almost any amount as they have long been considered safe.  However, these FDA decisions were made well before we knew very much about the health of the bowel wall and certainly how they might act in certain disorders such as CD.

There are many emulsifiers.  Below is a list of just a few of them.

• xanthan gum
• gum Arabic
• guar gum
• polysorbates
• lecithins – often from eggs
• carboxy methyl cellulose (CMC) – very common
• propyl hydroxyl methyl cellulose (PHMC)
• many other celluloses such as methyl cellulose, which is the ingredient in Citrucel

If you do not recognize the name of an ingredient in the packaged label, assume it may not be good for you.  Look it up on Wiki.  It may be an emulsifier.

The Mucous Biofilm

This subject is a bit medical but for a Crohn’s patient it is important.  There is a mucous layer that covers the entire inside lining of the gut.  Technically, it is known as a biofilm.  This is a thick tenacious mucous film that covers the lining of the gut.  It allows the absorption of all the good things we need such as calories, vitamins and minerals.  But, most importantly, it is the first line of defense against bacteria invading the wall of the intestine itself.  Invasion of the bowel wall is the first thing that occurs in Crohn’s disease.

So, an emulsifier that is added to a prepared, packaged or bottled food may have a bad effect on the mucous biofilm.  It may actually emulsify it.  Two different emulsifiers have been studied in the mice model.  One was the very commonly used emulsifier, carboxy methyl cellulose (CMC), and the other was a polysorbate.  In both instances, it was found that the emulsifier actually did injure or “emulsify” the mucous covering the lower bowel wall and allow bacteria to migrate through and cause an inflammatory process very similar to what happens in CD (2,3).  We really need to have a lot of medical research to know if these added chemicals in prepared foods are injurious to CD patients.  Like many of the chemicals that have been added to the environment or, in this instance foods, it might be better to just avoid them rather than wait many years to get a definitive answer.

Summary

• Shop for fresh foods and avoid, to the extent possible, prepared, packaged and bottled foods.
• Reduce animal protein, especially meat, to 50 grams a day, about the size of a deck of cards.
• Reduce animal and vegetable oil fats.
• Increase fresh or frozen vegetables, whole grains and, especially, fresh fruits.
• Learn about emulsifiers and other food additives.  To the extent possible, avoid them.
• Be sure your vitamin and mineral intake is adequate.
• Learn about prebiotics in certain foods and how they can shift the balance of bacteria in the
  gut from bad to good.
• Consider a prebiotic supplement such as Prebiotin.

References

1. Dietary intake and risk of developing inflammatory bowel disease: a systematic review of the literature.
Hou JK, et al.
Am J Gastroenterol 2011 Apr;106(4):563-73.
Conclusions: High dietary intakes of total fats, PUFAs (polyunsaturated fatty acids), omega-6 fatty acids, and meat were associated with an increased risk of CD (Crohn’s Disease) and UC (Ulcerative Colitis).  High fiber and fruit intakes were associated with decreased CD risk, and high vegetable intake was associated with decreased UC risk.

2. Bacterial overgrowth and inflammation of small intestine after carboxy methyl cellulose (CMC) ingestion in genetically susceptible mice.
Swidskinski A, et al.
Inflamm Bowel Dis 2009 Mar; 15(3):359-64.
Conclusions: The emulsifier carboxy methyl cellulose (CMC) induces bacterial overgrowth and small bowel inflammation in susceptible animals.  Because of its ubiquity in products and its unrestricted use in food of the industrial world, CMC is an ideal suspect to account for the rise of IBD (inflammatory bowel disease) in the 20th century.

3. Translocation (movement) of Crohn’s disease Escherichia coli (bacteria) across M-cells (intestinal mucous cells): contrasting effects of soluble plant fibers and emulsifiers.
Roberts CL, et al.
Gut, 2010 Oct;59(10):1331-9 Epub 2,010 Sep 2
Conclusions: Translocation of E coli (bacteria) across M-cells (intestinal mucous cells) is reduced by soluble plant fibers, such as inulin and oligofructose (Prebiotin), particularly plantain (bananas) and broccoli, but increased by the emulsifier Polysorbate-80.  These effects occur at relevant concentrations (meaning concentrations that are used in the typical prepared foods) and may contribute to the impact of dietary factors or Crohn’s disease pathogenesis.