Diet for Suspected Carbohydrate Maldigestion/Malabsorption

Here is a quick overview of foods that are allowed/not allowed when carbohydrate maldigestion/malabsorption is suspected.

What is carbohydrate maldigestion/malabsorption?
Many of us are familiar with lactose intolerance, which means the inability of the body to break down, to digest and to absorb lactose--which is a type of sugar or carbohydrate that is found in milk.  Inability to break down this type of carbohydrate causes gas, bloating and sometimes diarrhea.

While lactose intolerance is the most widely known carbohydrate maldigestion syndrome, other forms of maldigestion exist.  Some of the most common ones include the inability to properly break down the carbohydrates or the cellulose in vegetables and grains.    Animals and humans have different abilities to digest carbohydrates. For example, cows can easily digest grass and hay.  Humans on the other hand, cannot digest grass and hay, but there are plants--we call vegetables and grains--that we can digest and derive nutrition from.  However, not everybody's ability to digest vegetables is the same (similar to the idea that not everyone's ability to digest lactose is the same).

Below is a quick view guide of foods that are generally okay and generally "not allowed" when someone is doing an elimination-challenge diet to test the idea of carbohydrate malabsorption might be causing gastrointestinal problems.

If you have any questions about this diet, please add a comment below.



Quick View

	Generally Okay	Not Allowed	Notes
Meat and Fish	chicken, turkey, fish, beef, lamb, shellfish, scallops	Processed meats such as hot dogs, cold cuts, smoked foods, fast food type meats	Some good quality processed meats (there are many at Whole Foods) that do NOT have added sugar or carbohydrates may be allowed.  Read the label, if there are no or very low carbohydrates and sugars, then it should be okay.
Vegetables	Fresh or frozen, but all vegetables should be cooked: spinach, carrots, tomatoes, squash, beets, asparagus, cauliflower, eggplant, pumpkin, waterress, string beans, onions, garlic.	For some people, members of the brassica family may be harder to digest; a solution would be to cook them longer or eat smaller amounts--broccolli, kale, chard, cauliflower, bok choy.	No raw vegetables in the beginning. If you seem to have symptoms from a particular vegetable, cook them longer the next time to break down molecules.
Grains/Complex Carbs	None	No bread, rice, pasta, potato, sweet potato, quinoa, corn, barley, rye, amaranth, flour substitutes, couscous, garbanzo beans, hummus, yams, okra, mungbeans, soybeans--soy beans, soymilk, tempeh, tofu, seitan, etc	Lentils, split pea and white beans  may be allowed starting around month 2-3, if symptoms improve at that time. These should be soaked for 12-24 hrs (soaking water discarded) before cooking.  Note: I've had patients say that beans cause problems. If they do, please do not persist. But, I always encourage patients to make sure that the beans are cooked properly--they should be very tender. Invest in a good pressure cooker to achieve this.    Anecdotally, many are also able to tolerate quinoa.
Fruit	Ripe bananas (with brown spots on the skin; not fully ripened bananas contain a lot of starch/complex carbs); apples, pears, blueberries, strawberries If still having loose stools or diarrhea, it is best to avoid all fruits even those above. Start on fruits only once the symptoms have become stable.	Canned or dried fruit with added sugar/corn syrup/sweetener.	With active diarrhea, no raw fruits, except for ripe bananas.  If you find that you cannot tolerate fruit, you can poach them in hot water with some honey to further break down molecules. Limit to 1 cup of fruit a day because fruit contains sugar which can feed the microorganisms.
Dairy	Butter, ghee, some cream.	Milk, processed cheese, whey protein powder, mozzarella, ricotta, margarine, yogurt
Oils	Almost all oils are okay: olive oil, coconut oil, soybean oil, butter, corn oil
Nuts	Peanut butter, almond butter, almond flour, hazelnuts, pecans	Processed nuts or “honeyed” nuts that contain sugar or starch
Sweeteners	Honey	sugar, corn syrup, high fructose corn syrup, molasses, maple syrup, stevia, chocolate, carob, cocoa, sucralose or splenda
Spices	Almost all spices are allowed except for “pre-mixed” spices which contain sugar or starch or dextrin or modified starch or maltodextrin
Drinks	Water Tea Coffee-no sugar, some cream		If diarrhea has subsided, Diluted fruit juices (50-50) with no added sugars Very dry wine (because this means the sugars have been fermented into alcohol)-2 servings/week

Updates:

1.  I have a received some emails/comments with very specific questions about being able to eat this or that food item. I really appreciate these questions, specially when patients ask me during their visits, because I know that they're really thinking about the diet and are open-minded about it. It means that they are engaged and are considering it.  

I think that thinking of how to use diet to stay healthy when someone has Colitis is always a step in the right direction--I know that drugs, steroids and biologics do work for a good proportion of the time that they are taken--however, the issue is more about sustainability. I don't think it's a good idea to be on steroids for a long time or an indefinite period of time. There are just too many side effects and they are not sustainable for the health of the rest of the body. 

2. Specific food items. I often get asked by patients about specific food items that they really really like and will miss if they are on this diet. I understand that very much. Sometimes, the answer is pretty obvious that the food item in question is probably not a good idea--donuts, a type of cake they really enjoy from childhood.  However, there are many food items which are on the "do not eat" list which make me pause. An example would be sweet potatoes or potatoes in general. I would say most patients try it and they prove to themselves that it is not a good idea because they get gas and bloating or a stomachache from it. However, I do have patients who try it out and don't get many symptoms. Sometimes, I'll give them advice such as make sure it's cooked very well before you try it, so that the carbohydrates are more broken down into smaller molecules. 

I think the bottomline is, if you feel very very strongly about a particular food item, then you can try it and see. Sometimes, the answers are so clear that this food item is either fine or something that causes problems.  Also, there will be times, when the answer is not so clear. As a doctor, I would ask the patient to basically avoid that food item.