Okay, so we all know about lactose intolerance – and some IBS sufferers may also even be familiar with fructose intolerance – but what about SUCROSE intolerance? Yup; that’s a thing!
If you’re among the millions of people with irritable bowel syndrome (IBS) who doesn’t get any relief from a low FODMAP diet, and you suspect (or confirmed) you have a sucrose intolerance masquerading as IBS, a sucrose intolerance diet (aka the “sucrase-isomaltase deficiency diet”) could potentially be your ticket to IBS relief.
Disclaimer: This isn’t medical or nutrition advice; the information in this article is educational and generalized, NOT customized to your individual needs! Some or lots of the information in this article may or may not apply to you. Make sure you’re working with a registered dietitian and doctor who specialize in sucrase-isomaltase deficiency to receive custom clinical guidelines and the right protocols for YOU.
Affiliae disclosure: This article contains several affiliate links*. As an Amazon Associate, I may make a commission on qualifying purchases at no extra cost to you!
Table of Contents
What is sucrose?
Sucrose is the chemical name for “table sugar.” Chemically, sucrose is a disaccharide which is made up of equal parts glucose + fructose.
Sucrose in the diet
There are three main ways to consume sucrose in the diet:
- Adding sucrose-based sweeteners to coffee, tea, or recipes
- Consuming foods naturally high in sucrose (i.e. carrots, pineapple, starchy foods)
- Consuming processed foods made with high-sucrose sweeteners
(Get a comprehensive list of high-sucrose foods here.)
What is sucrose intolerance?
Much like a lactose intolerance or fructose intolerance, a sucrose intolerance is the inability to naturally break down sucrose in your intestines, because you’re lacking an intestinal brush border enzyme called sucrase-isomaltase. (1, 2)
Thus, a sucrose intolerance is caused by a sucrase-isomaltase deficiency. There are two sub-types of a sucrase-isomaltase deficiecy:
- Genetic, aka “congenital sucrase-isomaltase deficiency” (CSID)
- Acquired, or secondary sucrase-isomaltase deficiency
While the genetic sub-type is a bit self-explanatory, the secondary form of this enzyme deficiency is caused by another condition (such as small intestinal bacterial overgrowth (SIBO), celiac disease, Crohn’s disease, or ulcerative colitis) – all of which may wreak havoc on your intestinal brush border (the hub for digsetive enzyme production) if left unchecked for too long.
SIBO means bacteria have migrated into your intestines and are damaging the brush border of your intestinal tract. (This leads to an insufficient production and secretion of the sucrase-isomaltase enzyme over time.)
Celiac disease, Crohn’s, and colitis are all types of inflammatory bowel disease which may also potentially interfere with the brush border enzyme production in your intestines.
Sucrose intolerance is a common but little-known underlying root-cause of IBS which often flies under the radar.
It’s worth exploring, if you’ve ruled out inflammatory bowel disease (IBD) and you’re among the ~25% of IBS sufferers who didn’t see any improvement from following a low FODMAP diet. (3)
A person with a sucrase-isomaltase deficiency who consumes table sugar (or anything that contains sucrose) will have symptoms comparable to someone with lactose intolerance after drinking a big glass of milk.
Signs and symptoms
Unfortunately, sucrose intolerance is a lot more difficult to pinpoint than lactose intolerance, since sucrose is found in so many foods. As a result, this sub-group of individuals often end up spending many years suffering unnecessarily, due to a lack of clarity around what’s really going on in their bodies. (Learn more about how to recognize sucrose intolerance symptoms here.)
Sucrose intolerance treatment
Once you’ve determined (with help from your treatment team) that you do in fact have a sucrose intolerance from, the next step is to move forward with sucrose intolerance treatment.
If you’re working with a functional dietitian (or CSID dietitian), you’ll likely move through a variation of the 5R protocol for gut repair, with a sucrose intolerance diet (alongside special digestive enzymes such as Sucraid) being a primary intervention in the “Remove” and “Replace” phases of the 5R’s.
What’s a sucrose intolerance diet?
A sucrose intolerance diet is a type of IBS diet specifically intended for people with a sucrase-isomaltase deficiency.
This diet entails reducing/limiting your intake of high sucrose foods (which can’t be properly digested in your gut, leading to unwanted symptoms), while simultaneously leaning on more low sucrose foods in your diet.
Below are some general guidelines and a sample meal plan for those prescribed a sucrose intolerance diet. This is meant to be used as a resource, alongside working with a doctor and registered dietitian who specialize in sucrose intolerance – to make sure you’re getting everything you need from a nutritional standpoint!
Sucrose intolerance diet: general guidelines
- Before starting, even after a sucrase-isomaltase deficiency has been identified, make sure you have a healthy relationship with food, self-care, and body image to ensure that this diet does not spiral into disordered eating and/or a slew of nutritional deficiencies. (Work with an intuitive eating / Health at Every Size dietitian for this type of work.)
- The first/next step is to gradually start removing and replacing foods high in sucrose with lower sucrose alternatives. (Refer to the chart and sample meal plan below as a guide!)
- Make sure to continue eating a balanced diet and including every food group, so you’ll get enough macro- and micronutrients. Use the MyPlate as a visual if you aren’t sure where to start when it comes to food groups, ratios, and portion sizes. Your dietitian will also be able to help you in this department. 😉
- Log your food intake and track your symptoms, to get a better idea of which foods your body is tolerating best. (Have you checked out this IBS Food Diary* made by yours truly?!)
- Lean on digestive enzymes, probiotics, and other functional foods/ herbs / nutraceuticals as needed, to support your gut holistically.
- When your symptoms are under control and you’re having bowel movements that resemble mostly 3’s and 4’s on the Bristol Stool Chart, work with your dietitian to start gradually reintroducing foods higher in sucrose to see if you’ll be able to tolerate them in small to moderate quantities.
Sucrose Intolerance Diet Foods List
(Adapted from CSID Cares Food Composition Database & my clinical experience)
|Food Group / Category||LEAN ON THESE
(Low Sucrose Foods)
|LIMIT / MODERATE / TEST
(Moderate Sucrose Foods)
|REDUCE / AVOID (High Sucrose Foods)|
Citrus: oranges, grapefruit, clementines, tangerines, mandarin oranges, tangelos, etc.
Bell peppers (red, yellow, green)
Mung bean sprouts
Yellow squash (“summer squash”)
Yellow wax beans
|Grains / Starches||Amaranth
Buckwheat soba noodles
Coconut flour (for baking)
Rolled oats / unsweetened oatmeal
Whole rye bread
Corn / corn flour products
Breads, pastries (muffins, bagels, croissants, coffee cake, etc.)
Commercially made crackers, croutons, breadcrumbs
Granola, granola bars
Wheat flour / whole wheat
Butter / ghee
Oils (all kinds)
Sunflower seed oil
|Proteins (vegetarian)||Cheeses (all)
Chickpeas (“garbanzo beans”)
|Herbs / Spices
(Not enough research to determine whether any additional herbs are high in sucrose – listen to your body!)
|Drinks||Water (regular or carbonated)
Milk (cow’s, goat, Lactaid milk)
100% tomato juice
Green juice made with cucumber, spinach, ginger + lemon
Homemade lemonade/limeade sweetened with fructose/honey
Soda made with high fructose corn syrup
|Anything processed (check the ingredient list), for example:
Commercially-made coffee drinks / coffee creamers
Commercially-made meal replacement drinks/supplements (i.e. Boost, Ensure)
Juices made with high-sucrose fruits/veggies/sweeteners
Energy drinks or iced tea sweetened with high-sucrose sweeteners
Sodas or sports drinks with high-sucrose sweeteners
Sweetened nut milks
Lactose (milk sugar)
Monk fruit extract
Stevia leaf extract
High fructose corn syrup
Inverted sugar syrup / “invert sugar”
Maltose (malt sugar)
Sugar alcohols (sorbitol, mannitol, maltitol, xylitol, erythritol, lactitol)
|Coconut palm sugar / “coconut sugar”
Real maple syrup
Sugar in the Raw®
Primal Kitchen Mayonnaise
|Any food containing starch (flour), and/or “sugar” or “sucrose” or “maple syrup” or “coconut sugar” as an added ingredient:
Mainstream/commercial candy and chocolate
Most commercially made “health foods” – i.e. flavored yogurt, protein bars, protein shakes, protein powders
Maltodextrin (starch additive)
Mainstream condiments: ketchup sweet relish, barbeque sauce, bread & buter pickles, tomato sauce with added sugar
Commercially made salad dressings with added sugar
Processed meats cured with sugar (check ingredient list)
Sample low sucrose meal plan
(Reminder: this is just a SAMPLE meal plan of what a balanced day of low sucrose meals and snacks can look like. This is NOT customized to meet your individual needs and preferences. That is where a 1:1 dietitian comes into play!)
- Scrambled eggs with 1/2 cup cooked broccoli/spinach/mushrooms, 1 ounce cheese, and 1/4 to 1/2 fresh sliced avocado
- Side of 2 kiwifruit or other 1 serving of low sucrose fruit of choice
- Coffee or tea with optional drop of stevia leaf extract / monk fruit extract, splash of cream
- 1 cup full-fat plain yogurt with a dollop of raw honey, 1 to 2 tablespoons ground flaxseeds, and 1 cup strawberries
- Tuna salad with grapes recipe (sans pecans) in a lettuce wrap
- Vegetarian modification: swap tuna for hard-boiled eggs
- Optional – 1 Piece of Honey Mama’s Oregon Mint Cocoa Truffle Bar*
- ½ cup cottage cheese or 1 ounce hard cheese
- 1 cup cherries and/or 1 cup sliced cucumbers
- 2 cups cooked spaghetti squash
- 1/3 cup of this simple homemade tomato sauce (replace the onion with 1 bell pepper)
- 1/4 lb. grass-fed ground beef or ground turkey
- 1/2 cup cooked broccoli/spinach/mushrooms or other low sucrose veggie of choice
- 1/2 cup of this homemade ice cream (sweetened with raw honey)
- OR – this avocado cacao mousse (made with raw honey as the sweetener, and canned unsweetened coconut milk as the dairy sub)
One size doesn’t fit all
Keep in mind: gut health is complex! Your gut microbiome is as unique as your fingerprint. (Read more about “bio-individuality” here!)
Not everyone is going to react the same way to foods high/low in sucrose, so you’ll likely still require some level of customization on your sucrose intolerance diet.
- For example, people with lactose intolerance may need to find alternatives to dairy that contains lactose.
- Or if you’re vegetarian, you’ll need to work with a dietitian to make sure you’re getting enough protein.
- Or maybe, you just don’t like some of the foods listed in the above sample meal plan…
Bottom line: don’t try to do this alone! Work 1:1 with a registered dietitian to get the support you need in the realm of clinical nutrition and meal planning.
To learn more about how to navigate sucrose intolerance, you may want to check out the following articles:
- What is a Sucrose Intolerance and How Do You Know If You Have It?
- Understanding Congenital Sucrase-Isomaltase Deficiency (CSID): Causes, Symptoms, and Treatment
- How Does CSID Differ from Lactose Intolerance?
- Understanding the Genetics of CSID
- A Comprehensive List of Foods High In Sucrose
- Low Sucrose Foods List
- Why & How to Keep an IBS Food Diary
- What is a “Leaky Gut” and How Do You Know If You Have It?
- Food Allergy vs Intolerance vs Sensitivity
The sucrose intolerance diet / “sucrase-isomaltase deficiency diet” is very restive, since so many foods contain natural or added sources of sucrose. This diet is meant only for those with a diagnosed sucrase-isomaltase deficiency and subsequent sucrose intolerance.
The fundamental backbone of this diet is to plan balanced meals using mostly all low sucrose foods, while avoiding foods higher in sucrose. However, dietary restriction and avoidance of trigger-foods is only one component of a holistic nutrition protocol for gut health.
Tracking your food intake and symptoms will also help you and your treatment team to determine your body’s unique tolerance thresholds to foods containing varying amounts of sucrose.
Working with a functional dietitian to receive custom nutritional & supplement guidance (and to possibly run other types of functional nutrition tests, as needed) is not optional!
I get it… this is a LOT to process, and probably a lot of new information to learn & remember, if you’re in the early stages of navigating a sucrose intolerance diet!
In case you’re feeling *slightly* or VERY overwhelmed, I created a convenient printable list of low sucrose foods & high sucrose foods for you to refer back to as needed.
Just click on the link above, or the image below, to sign up & snag your copy fo’ free!
Knowledge is power, so please share this post with others in your world who are navigating sucrase-isomaltase deficiency and would like to learn more.
XO – Jenna