10 Surprising Foods to Avoid With CSID

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Congenital sucrase-isomaltase disease (CSID) is a digestive disorder characterized by a deficiency in or absence of sucrase and isomaltase.

Your body needs these enzymes to break down sucrose (table sugar) and isomaltose (a type of starch) — both of which are disaccharides or double sugars — into single sugar molecules to be absorbed.

A deficiency in these enzymes allows sucrose and isomaltose to go undigested, causing diarrhea, abdominal pain, bloating, and other uncomfortable digestive symptoms.

Avoiding or limiting foods rich in sucrose and isomaltose alleviates these symptoms, but doing so can be challenging since many foods contain them, including many that you wouldn’t expect.

This article lists 10 surprising foods rich in sucrose or isomaltose to avoid with CSID.

1. Milk

Milk doesn’t contain sucrose or isomaltose.

However, one observational study found that 25% of people with CSID were also lactose intolerant (1).

Therefore, if you’re already closely following a CSID diet but still experiencing severe digestive symptoms, you may be lactose intolerant.

In this case, eliminating milk while continuing to restrict sucrose and isomaltose may improve your symptoms.

Lactose or milk sugar is a FODMAP and may also prove symptoms in people with irritable bowel syndrome (IBS) and small intestinal bacterial overgrowth (SIBO).

Having CSID may increase your risk for SIBO.

2. Chinese chicken

Chicken breast is a safe choice with CSID but not when it’s battered, fried, and coated in a sucrose-rich sauce.

Just one order of orange chicken provides 80 grams of sucrose and close to 70 grams of starch (2).

Sweet and sour or sesame chicken is no better so it’s best to skip the Chinese buffet line.

3. Barbeque sauce

The sweetness of barbeque sauce comes from its high sucrose content.

One 2-tablespoon (16-gram) serving of barbeque sauce provides around 6 grams of sucrose.

You may be able to tolerate some barbeque sauce but be mindful of your portion.

Alternatively, there are plenty of no-sugar-added options like this one from Sweet Baby Ray’s.

4. Coleslaw

Coleslaw is a great side dish to round out a meal.

However, just one-half cup of coleslaw provides around 10 grams of sucrose, which may be just enough to provoke your symptoms (2).

Fortunately, you can use sucrose-free coleslaw dressing like this one from G Hughes or make your own using an artificial sweetener like sucralose (Splenda).

Or, as an alternative to artificial sweeteners, you can use fructose or dextrose to replace sucrose in your coleslaw dressing recipe.

5. Peanut butter

Peanut butter is a versatile, delicious kitchen staple.

While most of its calories come from fat, most varieties contain around 3 grams of sucrose per 2-tablespoon (33-gram) serving (2).

Sticking with this serving size might not trigger your symptoms but it may if you eat it with other foods rich in sucrose or starch.

You can shave a few grams of sucrose by opting for a powdered peanut butter product like Naked PB.

Almond butter contains a similar amount of sucrose as peanut butter and should also be limited.

6. Processed meats

Meat that has been salted, smoked, salted, cured, dried, or canned is considered processed.

Examples of processed meats include sausages, hot dogs, salami, ham, and lunch meats.

Some processed meats can have several grams of sucrose per serving since manufacturers add it as part of the curing and preservation process.

Always check the nutrition label as some provide more sucrose than others.

7. Dried pasta mixes

Packaged foods like dried pasta mixes can be a sneaky source of many additives — including sucrose and isomaltose.

It’s the seasonings and sauces of these mixes that contain sucrose and isomaltose, so stick with plain pasta if you can tolerate it.

Store-bought pasta sauces are also rich in sucrose so look for no-added-sugar marinara sauces like this one from Hoboken Farms.

It’s more difficult to find packeted sauce mixes that are low in sucrose or isomaltose.

8. Pistachios

Nuts naturally contain a small amount of sugar in the form of sucrose.

Compared with other nuts, pistachios tend to contain high amounts of sucrose.

A one-ounce (about 49 kernels) serving of pistachios provides about 8 grams of sucrose (2).

The same one-ounce serving of pecans, macadamia nuts, and walnuts provides half the sucrose as pistachios.

9. Flavored oatmeals

If you can tolerate it, oatmeal is a filling, heart-healthy food.

However, you should stick with plain quick or old-fashioned oats since the flavored oatmeal packets provide upwards of 10 grams of sucrose per serving (2).

Use a sugar substitute or dextrose to sweeten your oatmeal.

You can also add sweetness by topping your oatmeal with low-sucrose fruits like berries.

10. Beer

Maltose is the primary sugar in beer.

Maltose and isomaltose are similar in that they are composed of two glucose molecules but they differ in how the molecules are joined.

Due to their similarities, people with CSID also have low amounts of maltose — the enzyme necessary to digest maltose.

For this reason, foods and beverages rich in maltose like beer can trigger digestive symptoms.

The bottom line

Restricting sucrose and isomaltose is the primary way to manage the uncomfortable digestive symptoms of CSID.

Many foods that you might not expect to contain sucrose, isomaltose, or both, include Chinese chicken, barbeque sauce, coleslaw, peanut butter, and processed meats.

Other sources include dried pasta mixes, pistachios, and flavored oatmeal.

Because many people with CSID are lactose intolerant, you may also need to limit milk and milk products to relieve your digestive symptoms.

Taking Sucraid, an enzyme replacement for sucrase, can ease symptoms and allow for a more flexible diet.

You can learn more about Sucraid for CSID here.