Sugar and IBS: 10 interesting Facts you Should Know.

The relation between sugar and IBS is quite confusing.

A piece of strong evidence exists that some types of sugar may harm your IBS. Deciding whether to withdraw or continue eating sugar with IBS is challenging.

In this article, We will simplify to you the relation between IBS and sugar. Also, I will explain how to deal with sugar while you have IBS:

  • What types of sugar do you have to cut out.
  • What types of sugar to use with caution.
  • How to experiment with sugar elimination for the best results.

IBS and Sugar Facts And Tips:

1- Sugar is not a single entity. [REF]

Let’s define things, sugar is a carbohydrate. The traditional type of sugar is table sugar (cane sugar). This is not the only type of sugar present out there.

Cane sugar is formed mainly from sucrose sugar. Sucrose sugar is present in sugarcane, sugar beets. It also exists in almost every other plant but small amounts.

But, sucrose is not the only type of sugar to be concerned with if you have IBS.

Sugar types affect IBS differently

Other types of sugar exist, they include:

1- Fructose: found in fruits and honey.

2- Lactose: found mainly in milk (it is made mainly from glucose and galactose)

3- Galactose: found in all dairy products, including milk, ice cream, yogurt, cheese.

4- Glucose: a simple sugar present in honey, fruits, and vegetable. (usually present together with other sugars and not present alone).

5- Polyols (sugaroalcohols): sugar substitutes like sorbitol, xylitol, mannitol. They are present in certain fruits and artificial sweeteners.

Each type of sugar is slightly different. Also, they react differently to Your IBS.

2- Different sugars have different impacts on your IBS.

Some sugars are FODMAPs. FODMAPs are a group of carbohydrates that proved to trigger your IBS.

  • The letter D in FODMAP refers to the disaccharide sugar Lactose.
  • The letter M refers to the monosaccharide sugar Fructose.
  • The letter P refers to sugar alcoholsoor polyols.

On the other hand, Sucrose (table sugar) is low in FODMAP. Although there is evidence that it may trigger your IBS. Sucrose contains equal amounts of fructose and glucose, glucose is our friend, it is readily absorbed and doesn’t cause digestive problems.

When consumed in moderate amounts, Cane sugar can be tolerated.

3- The connection between sugar and IBS. [ref]

Theory 1: Sugar intolerance.

IBS is linked to the malabsorption of one or more of the sugar types enlisted above. Most importantly FODMAP sugars like lactose, fructose, and sugaroalcohol.

This study on 239 patients with functional bowel disorders (94 IBS patients and 145 patients with other functional gut disorders) found that:

  • More than 60% of patients have malabsorption of multiple types of sugar (fructose, sorbitol, and lactose).
  • 82% of IBS patients have lactose malabsorption.
  • 44% of IBS patients have fructose malabsorption.
  • Only 7% have normal sugar absorption.
  • And more importantly, 56% of IBS patients showed marked improvement in their symptoms after cutting these sugars.

So, it is clear that sugar and IBS are closely connected. Withdrawing sugar from your food may benefit your IBS.

sugar malabsorption and ibs


Theory 2: SIBO, not sugar intolerance. [REF]

Does another study suggest that the connection between sugar and IBS is through what so called small Intestinal Bacterial Over-Growth (SIBO).

The study suggests that the overgrowth of bacteria inside your small intestine will result in over-fermentation of poorly absorbable sugars like lactose and fructose.

So, Ingestion of sugars >> rapid fermentation by small intestinal bacteria >> gas and bloating.

Also, Researchers used antibiotics to kill these over-grown bacteria. And this improved the response to sugar ingestion.

SIBO may be the cause of IBS symptoms related to sugar ingestion (and not a real sugar intolerance). The connection between SIBO and IBS is still under investigation.

4- One food can contain more than one type of sugar.

Unfortunately, most of the food we consume contains more than one type of sugar. Making it difficult to define the specific type of sugar triggering our IBS.

Foods like fruits, dairy, and honey contain combinations of more than one type of sugar. An example is  Honey which contains: [ref]

  • Fructose: 38.2%
  • Glucose: 31.3%
  • Maltose: 7.1%
  • Sucrose: 1.3%
  • Water: 17.2%
  • Higher sugars: 1.5%
  • Ash: 0.2%
  • Other/undetermined: 3.2%



High fructose in Honey may hurt your IBS. The same goes for many fruits, so it is difficult to track every food. The process of dealing with sugar and IBS needs trial and error. Every IBS patient is different.

Here is a summary of different sugar types and their effect on your IBS:

Sugar typeFound inEffect on IBS
1- Sucrose (Table sugar, cane sugar)Made from sugarcane or sugar beets.It can be tolerable if consumed in small amounts. (data is controversial)
2- LactoseFound in milk & other dairy productsHigh FODMAP, Bad for IBS.
3- FructoseMany fruits like apples, high fructose corn syrup, and honey.High FODMAP, Bad for IBS.
4- Sugaroalcohols (Polyols)Some fruits like apple and apricot, artificial sweeteners, and some vegetables like cauliflower.High FODMAP, Bad for IBS.
5- GlucoseNot present in pure form, usually combined with other types of sugar in fruits and vegs.Ok with IBS.


5- Table sugar (cane sugar) and IBS:

The conventional table sugar is made mainly from sugar cane or sugar beet. Cane sugar consists of Sucrose. Sucrose is low in FODMAP. When used in moderation can be tolerated with your IBS.

However, some recent data suggest that cutting sucrose may improve your IBS symptoms.

This recent 2019 study suggests that reducing Starch and Sucrose in diet improved IBS symptoms in 50% of patients.

cane sugar and IBS

So, data is unclear about the relation between sucrose sugar and IBS.

Shall I take cane sugar or not?

Although low in FODMAP, We need more research about table sugar and IBS. Some people with IBS tolerate sucrose, while others cannot.

If you have persistent symptoms, The best option is to try to eliminate cane sugar for 2 weeks. If Your IBS symptoms improve, try to reintroduce cane sugar again in small amounts. And stick to the least tolerable amount.

6- Fructose and IBS.

Fructose is a high FODMAP sugar. Fructose may trigger your IBS symptoms. Reducing foods high in fructose may result in an improvement in your IBS symptoms.

The foods High in Fructose are:

1- Fruits:  Apple, mango, nashi, pear, tinned fruit in natural juice, and watermelon.

2- Honey.

3- High fructose corn syrup.

4- Concentrated fruit sources, large dried fruit, and fruit juice.

7- Lactose and IBS.

Lactose is the chief sugar present in milk and dairy products. Many studies linked IBS to some sort of lactose intolerance [ref]. Lactose is a FODMAP. Thus reducing a diet rich in lactose may benefit your IBS.

Common food sources of lactose include:

1- Milk: from cows, goats, or sheep.

2- Custard, Ice cream.

3- Yogurt: Yes, yogurt can hurt your IBS. because it is rich in lactose.

4- Cheese: especially soft Unripened cheese like collage cheese.

A trial of lactose avoidance may help to improve your IBS symptoms.

8- Sugar substitutes and IBS.

Sugaroalcohols (polyols) are high FODMAP. Avoid them completely as they may worsen your IBS.

Polyols present in:

1- Fruits: apple, apricot, avocado, blackberry, cherry, lychee, peach, pear, prune, and watermelon.

2- vegetables: cauliflower, bell pepper, sweet corn, and mushroom.

3- Artificial sweeteners: Sorbitol, mannitol, Maltitol, and xylitol.

9- Experimenting is the key to dealing with sugar and IBS.

To solve the puzzle of sugar and IBS, you have to experiment. Not all IBS patients benefit from cutting down all sugar. So, try an elimination diet plan for two weeks as follows:

  • Cut all sugar from the diet (cane sugar, fructose, lactose, and sugar substitutes) for 6-8 weeks (better to have a complete low FODMAP diet plan with the aid of a dietitian).
  • Keep a food diary for your foods and symptoms.
  • Try to eat home-cooked foods to gain control over food ingredients.
  • After 2 weeks of elimination, try to reintroduce sugar, one type at a time, and record your symptoms.
  • Always consult your doctor or certified dietitian.
  • Don’t try the elimination diet if you have diabetes or any other medical condition unless guided by your doctor or dietitian.

10- What sugars to try with Your IBS?

If you have to use sugar while you have IBS. you can try small to moderate amounts of the sugar types enlisted below. [ref]

Basically, they are low in FODMAP. With fewer intolerance events. But still can cause symptoms, especially if used in excess.

1- Common table sugar (cane sugar or beet sugar).

2- Brown sugar: Unrefined sugar that retains some molasses.

3- Golden syrup: low in fodmap, can be used in small amounts. It can be used in baking and as a substitute for honey recipes.

4- Maple syrup: Made from various sugars. A safe source of sweeteners.

Take-Home messages:

  • A piece of evidence exists that sugar can affect your IBS.
  • Sugar types are different: fructose, lactose, and sugar substitutes are high in fodmap, Mostly they will hurt your IBS.
  • Table sugar (cane sugar) can be tolerable if used in moderation (although some data suggest the opposite).
  • So, trial and error with an elimination diet may be your only solution to deal with sugar and IBS.