What Is Carbohydrate Intolerance? Causes, Symptoms, & More

What Is Carbohydrate Intolerance? Causes, Symptoms, and How To Manage

Carbohydrate intolerance, you’ve likely heard of it, but what exactly does it mean? It’s become a topic of interest as more people face tummy troubles and health concerns related to their carb consumption. This condition, sometimes misunderstood or misdiagnosed, can truly throw a wrench into a person’s daily life; hence, it’s of utmost importance to identify and manage it properly.

Image of strawberry waffles on a plate. Image source: Unsplash
Image of strawberry waffles on a plate. Source: Unsplash

What is carbohydrate intolerance? Carbohydrate intolerance is a condition in which an individual experiences difficulty digesting certain carbohydrates, leading to uncomfortable symptoms such as bloating, gas, and abdominal pain. The severity of the intolerance can vary from person to person.

What is carbohydrate intolerance? 

Carbohydrate intolerance is a condition where the body has difficulty digesting certain carbohydrates due to a lack of one or more intestinal enzymes. This inability to digest carbs can occur because of increased consumption of sugars and carbs, a genetic deficiency of enzymes, or as a side effect of gastrointestinal disease.

Symptoms may include diarrhea, abdominal distention, and flatulence, and it is diagnosed clinically and by a hydrogen breath test. Treatment involves removing the causative disaccharide from the diet. Carbohydrate intolerance can also affect energy levels due to blood sugar spikes and lows caused by inefficient absorption or inability to use their energy effectively.

What causes carbohydrate intolerance?

Carbohydrate intolerance is caused by the inability to digest certain carbohydrates due to various factors. Let’s examine these factors more closely:

1. Lack of one or more intestinal enzymes

The primary cause of carbohydrate intolerance is the lack of enzymes required to break down certain carbohydrates in the digestive system. The primary enzymes responsible for breaking down carbohydrates in the digestive system are amylase, maltase, lactase, and sucrase.

A deficiency in any of these enzymes can lead to carbohydrate intolerance, causing symptoms like bloating, gas, abdominal pain, and diarrhea after consuming foods rich in specific carbohydrates.

2. Increased consumption of sugars and carbs

Overconsumption of sugars and carbohydrates can contribute to carbohydrate intolerance by overwhelming the body’s ability to process and metabolize these nutrients.

Image of strawberries and a spoon full of sugar. Image source: Pexels
Image of strawberries and a spoon full of sugar. Image source: Pexels

[Related: Good Carbs vs Bad Carbs: Surprising Facts You Need to Know]

3. Genetic deficiency of enzymes

Some individuals may have a genetic deficiency of specific enzymes needed to digest certain carbohydrates, making it difficult for their bodies to break down and absorb these nutrients.

4. Gastrointestinal disease

Malabsorption of certain carbohydrates can occur as a side effect of gastrointestinal diseases, which can impair the normal function of the digestive system and lead to carbohydrate intolerance.

5. Carbohydrate metabolism disorders

Certain disorders that affect carbohydrate metabolism can result in carbohydrate intolerance by disrupting the body’s ability to process carbohydrates and use them for energy.

6. Insulin resistance

Insulin resistance, where the body’s cells become less responsive to the hormone insulin, can lead to carbohydrate intolerance as the body struggles to regulate blood sugar levels effectively.

What are the common symptoms of carbohydrate intolerance?

Common symptoms of carbohydrate intolerance include the following:

1. Diarrhea

Difficulty in digesting carbohydrates can lead to diarrhea as the undigested carbohydrates pass through the digestive system.

2. Abdominal distention

Carbohydrate intolerance can cause abdominal distention or bloating as a result of the fermentation of undigested carbohydrates in the gut.

3. Flatulence

The fermentation of carbohydrates in the gut can also lead to the production of gas, causing flatulence.

4. Increased blood sugar levels

When the body fails to break down and digest carbohydrates properly, it can cause an increase in blood glucose levels.

5. Weight gain

Carbohydrate intolerance can contribute to weight gain, as the body struggles to process and use the energy from carbohydrates effectively.

6. Fatigue

Inefficient absorption or utilization of carbohydrates can lead to blood sugar spikes and lows, affecting energy levels and causing fatigue

How is carbohydrate intolerance diagnosed?

Carbohydrate intolerance is diagnosed clinically and through a hydrogen breath test. The hydrogen breath test measures the amount of hydrogen in the breath, which can indicate if there is an issue with carbohydrate digestion. In cases of lactose intolerance, a specific example of carbohydrate intolerance, the diagnosis can be suggested if the stool from chronic or intermittent diarrhea is acidic (pH 6) and can be confirmed by a hydrogen breath test or a lactose tolerance test.

What are the treatment options for carbohydrate intolerance?

The primary treatment option for carbohydrate intolerance is the removal of the causative disaccharide from the diet. This means identifying the specific carbohydrates that an individual cannot digest and eliminating or reducing their intake of those carbohydrates. In some cases, a person with carbohydrate intolerance may also benefit from certain enzyme supplements to help digest the specific carbohydrates they are intolerant to.

How to deal with carbohydrate intolerance?

To deal with carbohydrate intolerance, follow these steps:

1. Remove the causative disaccharide from your diet

Identify the specific carbohydrates that you cannot digest and eliminate or reduce their intake. This may involve avoiding certain foods or food groups that are high in problematic carbohydrates.

2. Monitor your blood sugar levels

Carbohydrate intolerance can lead to increased blood sugar levels. Keeping track of your blood sugar can help you understand how different foods affect your body and make adjustments to your diet accordingly.

3. Maintain a balanced diet

While avoiding the specific carbohydrates causing your intolerance, ensure you are still consuming a balanced diet with adequate nutrients, including other sources of carbohydrates, proteins, and fats.

4. Manage your energy levels

Carbohydrate intolerance can affect energy levels due to blood sugar spikes and lows caused by not absorbing carbs efficiently or not being able to use their energy effectively. Adjust your meal timing, portion sizes, and food choices to help maintain stable energy levels throughout the day.

5. Consult a healthcare professional

Work with a healthcare professional, such as a nutritionist or dietitian, to create a personalized dietary plan.They can help you identify alternative food sources and make recommendations for enzyme supplements if necessary.

Remember that managing carbohydrate intolerance is a personalized process, and what works for one person may not work for another. It’s essential to monitor your symptoms and adjust your dietary and lifestyle habits accordingly.

Frequently asked questions (FAQ)

Got more questions about carbohydrate intolerance? Check out some commonly asked questions about this topic below.

What are the common symptoms of carbohydrate intolerance?

Carbohydrate intolerance can manifest in various ways, with symptoms ranging from mild to severe. Some common symptoms include bloating, gas, abdominal pain, diarrhea, and constipation. You may also experience fatigue, brain fog, and difficulty concentrating after consuming foods high in carbohydrates.

Are there any specific tests to diagnose carbohydrate intolerance?

Yes, there are specific tests available to diagnose carbohydrate intolerance. These tests often involve a breath test, where the patient consumes a carbohydrate-rich food or drink, and then their breath is analyzed for the presence of certain gases. Another common test is an oral glucose tolerance test, which involves drinking a sugary solution and then having blood samples taken at regular intervals to measure blood sugar levels. It’s essential to consult with a healthcare professional if you suspect you have carbohydrate intolerance.

Can carbohydrate intolerance be treated or managed?

Carbohydrate intolerance can be effectively managed with dietary modifications and lifestyle changes. Those with the condition should focus on reducing their intake of problematic carbohydrates and opting for low-carb or carb-free alternatives. In some cases, supplements or medications may be prescribed to help alleviate symptoms or improve digestion. It’s crucial to work with a healthcare professional to create an individualized treatment plan tailored to your specific needs.

Final Word

With a growing number of people experiencing discomfort and health issues related to carb consumption, it’s essential to recognize the symptoms, causes, and treatments for this condition. By making the necessary dietary and lifestyle adjustments, you can better manage carbohydrate intolerance and lead a healthier, more comfortable life.

If this article has been helpful to you, don’t hesitate to share it with a friend, and remember to explore this blog for more useful insights into health and wellness. Stay informed and take control of your well-being!


Yuri Elkaim is one of the world’s most trusted health and fitness experts. A former pro soccer player turned NYT bestselling author of The All-Day Energy Diet and The All-Day Fat Burning Diet, his clear, science-backed advice has transformed the lives of more than 500,000 men and women and he’s on a mission to help 100 million people by 2040. Read his inspiring story, “From Soccer to Bed to No Hair on My Head” that started it all.