How To Test or Identify That You Are Intolerant to Sugar

How To Test or Identify That You Are Intolerant to Sugar

Table of Contents

Sugar intolerance is a relatively common health concern that affects a significant portion of the population. As our diets have become increasingly laden with sugars in various forms, ranging from sucrose and fructose to high-fructose corn syrup, instances of sugar intolerance have risen. This makes it essential for people to be aware of the signs and symptoms associated with sugar intolerance.

Identifying sugar intolerance is essential not only for preventing discomfort and digestive distress but also for safeguarding long-term health. Undiagnosed and untreated sugar intolerance can lead to various health complications, including digestive issues, nutritional deficiencies, and an increased risk of certain chronic diseases. Therefore, understanding how to test for or identify sugar intolerance is paramount.

In this article, we will delve into the intricacies of sugar intolerance, exploring its causes, symptoms, and potential genetic factors. We will provide you with actionable steps to identify whether you may be intolerant to sugar. Moreover, we'll discuss the role of genetics in sugar intolerance and the importance of seeking professional guidance for accurate diagnosis and effective management.

Understanding Sugar Intolerance

Understanding Sugar Intolerance

Sugar intolerance, also known as sugar sensitivity or sugar malabsorption, refers to the body's inability to properly digest and absorb certain types of sugars. This condition primarily affects the digestive system, leading to a range of uncomfortable symptoms when consuming foods or beverages containing these sugars.

Sugar intolerance can be triggered by various sugars, including:

  • Lactose: Found in dairy products.
  • Fructose: Naturally occurring in fruits and added to many processed foods as high-fructose corn syrup.
  • Sucrose: Common table sugar, composed of glucose and fructose.
  • Sorbitol and Mannitol: Sugar alcohols used as sweeteners in sugar-free products.

Common Symptoms of Sugar Intolerance

The symptoms of sugar intolerance can indeed vary widely from person to person, making it important to be attentive to your body's signals and recognize the common indicators that may suggest you have a problem with sugar digestion. Here, we'll delve deeper into these symptoms to provide a more comprehensive understanding:

  • Abdominal Pain and Cramping

Abdominal pain and cramping are hallmark symptoms of sugar intolerance. This discomfort typically arises because undigested sugars can ferment in the gut, leading to the production of gas and causing the intestinal walls to stretch, resulting in pain and cramps. These sensations are often described as sharp or dull, and they may occur anywhere in the abdominal region.

  • Gas and Bloating

Gas and bloating often accompany sugar intolerance and can be particularly uncomfortable. When sugars are not properly digested, they provide a source of nourishment for gut bacteria. These bacteria produce gas as they break down the sugars, leading to excessive flatulence and a sensation of fullness or bloating in the abdomen. This can cause your belly to feel distended and uncomfortable.

  • Diarrhea

Diarrhea is a common digestive symptom associated with sugar intolerance. It occurs when undigested sugars draw excess water into the intestines and stimulate bowel movements. This can result in loose, watery stools and frequent trips to the bathroom. Diarrhea can be particularly disruptive to daily life and can lead to dehydration if not managed properly.

  • Nausea

Nausea is another symptom of sugar intolerance. This queasy feeling can occur after consuming foods or drinks high in the sugars that trigger intolerance. Nausea may be accompanied by a sensation of unease and may even lead to vomiting in some cases.

  • Headaches

Headaches can be an indirect symptom of sugar intolerance. The rapid changes in blood sugar levels that occur when certain sugars are not properly absorbed can lead to headaches or migraines in susceptible people. These headaches are often described as throbbing and can be accompanied by sensitivity to light and sound.

  • Fatigue

Fatigue is a less obvious but significant symptom of sugar intolerance. When your digestive system is struggling to break down and absorb sugars, it can lead to nutritional deficiencies and malabsorption of essential nutrients. This, in turn, can result in a persistent feeling of tiredness and low energy levels.

How Sugar Intolerance Differs from Other Conditions (e.g., Diabetes)

How Sugar Intolerance Differs from Other Conditions

It's essential to differentiate between sugar intolerance and other conditions like diabetes. Understanding these differences is important for accurate self-assessment. While both involve sugar metabolism, they are distinct:

  • Sugar Intolerance: Primarily affects digestion and absorption, leading to gastrointestinal symptoms.
  • Diabetes: Involves issues with insulin production or utilization, resulting in elevated blood sugar levels and various systemic effects.

The Role of Genetics

Genetics plays a significant role in sugar intolerance. Some people inherit genetic variations that make them more prone to developing sugar intolerance. These variations can affect the enzymes responsible for breaking down specific sugars in the digestive tract.

Family history can be a valuable clue when assessing your risk of sugar intolerance. If close family members have experienced sugar-related digestive issues, it increases the likelihood that you may also have a genetic predisposition to sugar intolerance.

Advances in genetic testing now allow people to explore their genetic makeup for potential markers of sugar intolerance. While genetic testing can provide insights, it's important to remember that the presence of genetic variations doesn't guarantee intolerance; it merely indicates an increased risk.

Identifying Sugar Intolerance

Keeping a Food Diary

One of the initial steps in identifying sugar intolerance is keeping a detailed food diary. Record everything you eat and drink, paying special attention to items containing sugars, sugar alcohols, and artificial sweeteners. Note any symptoms you experience, along with their severity and timing. This will help identify patterns and potential triggers.

Elimination Diet

An elimination diet can be an effective method for identifying sugar intolerance. Remove all sources of the suspected sugar(s) from your diet for a specific period, usually 2-4 weeks. Gradually reintroduce the eliminated sugars one at a time, observing how each affects your symptoms. If symptoms recur with a particular sugar, it may indicate intolerance.


While keeping a food diary and implementing an elimination diet can be valuable steps in identifying sugar intolerance, consulting with a healthcare professional is essential for a more accurate and comprehensive diagnosis. They can recommend and perform specific medical tests and diagnostic tools to confirm your condition. Here are some of the key methods used:

Breath Tests for Sugar Malabsorption

Breath Tests for Sugar Malabsorption

Breath tests are a non-invasive and commonly used diagnostic tool for sugar malabsorption. These tests are especially useful for detecting intolerance to sugars like lactose and fructose. Here's how they work:

  • Lactose Breath Test: For suspected lactose intolerance, you consume a lactose-containing solution, and then your breath is analyzed at regular intervals. Elevated levels of certain gases in your breath indicate that the lactose was not properly digested and absorbed.
  • Fructose Breath Test: A similar process is used to diagnose fructose intolerance. After consuming a fructose solution, the levels of specific gases in your breath are monitored over time.

The presence of excess gases in your breath suggests that the sugars were not absorbed as they should have been, indicating sugar intolerance.

Blood Tests to Measure Glucose Levels

Blood tests can provide valuable insights into how your body handles sugar metabolism. A glucose tolerance test is one such blood test that may be recommended by your healthcare provider. During this test:

  • You consume a specific amount of glucose (usually a sugary solution).
  • Blood samples are taken at regular intervals to measure your blood sugar levels.
  • Your healthcare provider assesses how your body responds to the sugar load, checking for any abnormal spikes or drops in blood sugar levels.

This test can help diagnose conditions like glucose malabsorption or insulin resistance, which can contribute to sugar intolerance.

Other Relevant Medical Tests

Depending on your specific symptoms and medical history, your healthcare provider may recommend additional tests, such as stool tests, endoscopy, or imaging studies like ultrasound or MRI. These tests can help identify any underlying gastrointestinal conditions or complications related to sugar intolerance.

Coping with Sugar Intolerance

Coping with Sugar Intolerance

Dietary Adjustments

Once you've identified sugar intolerance, making dietary adjustments is essential for managing your condition effectively:

  • Reducing Sugar Intake

Minimize or eliminate foods and drinks that contain sugars you are intolerant to. This may include avoiding certain  fruits, dairy products, sugary snacks, and processed foods.

  • Choosing Low-Sugar Alternatives

Opt for sugar-free or low-sugar alternatives when available. Be cautious with artificial sweeteners, as some people with sugar intolerance may also react negatively to these.

Meal Planning and Reading Labels

Become adept at reading food labels to identify hidden sugars. Sugar can hide under various names, such as sucrose, fructose, glucose, and high-fructose corn syrup. When meal planning, focus on whole, unprocessed foods to reduce your sugar intake.

Managing Sugar Cravings and Emotional Aspects

Sugar cravings can be challenging to manage. Learning strategies to cope with cravings, such as finding alternative snacks or practicing mindful eating, can be beneficial. Additionally, addressing the emotional aspects of dietary changes and seeking support from friends and family can make the adjustment easier.

Potential Complications

It's not uncommon for people with sugar intolerance to have coexisting conditions like irritable bowel syndrome (IBS). Recognizing and managing these conditions alongside sugar intolerance is essential for overall well-being. If left untreated, sugar intolerance can lead to several long-term health issues, including:

  • Nutritional deficiencies: Difficulty absorbing certain sugars may impact your ability to absorb essential nutrients.
  • Weight management: Sugar intolerance can contribute to weight gain if not managed properly.
  • Chronic conditions: There is evidence linking untreated sugar intolerance to irritable bowel syndrome (IBS) and other gastrointestinal disorders.

Sugar intolerance can affect your quality of life, leading to discomfort, stress, and dietary restrictions. Understanding the potential complications and addressing them proactively can help you lead a healthier and more fulfilling life.

Lifestyle Changes and Treatment Options

Lifestyle Changes and Treatment Options

Lifestyle Modifications to Manage Sugar Intolerance

In addition to dietary adjustments, consider the following lifestyle changes:

  • Regular exercise: Physical activity can help regulate blood sugar levels and improve digestive health.
  • Stress management: Stress can exacerbate digestive symptoms, so incorporating stress-reduction techniques like meditation or yoga can be beneficial.
  • Adequate hydration: Staying hydrated supports overall digestive health.

Medications and Supplements

In some cases, healthcare professionals may recommend medications or supplements to manage sugar intolerance symptoms. These could include enzyme supplements or medications that target specific aspects of sugar metabolism.

Alternative Therapies and Their Effectiveness

Some people find relief from sugar intolerance symptoms through alternative therapies such as acupuncture, probiotics, or herbal remedies. However, it's necessary to consult with a healthcare provider before pursuing these options to ensure they are safe and appropriate for your specific situation.

Prevention and Future Considerations

If you have a family history of sugar intolerance, you may be concerned about your children's risk. While genetics play a role, promoting a balanced diet with limited sugar consumption from an early age can help reduce the likelihood of developing sugar intolerance.

The field of nutrition and digestive health is continuously evolving. Stay informed about the latest research and advancements related to sugar intolerance, as new treatments and diagnostic tools may become available over time.

Make sure to schedule regular check-ups with your healthcare provider to monitor your condition and discuss any changes in symptoms or dietary needs. Staying proactive in managing sugar intolerance can lead to a healthier and more comfortable life.


Sugar intolerance is a prevalent condition that affects people worldwide, impacting their digestive health and overall well-being. Acknowledging the potential complications of untreated sugar intolerance and addressing coexisting conditions like irritable bowel syndrome is vital for long-term health and well-being. Lifestyle changes, such as regular exercise, stress management, and hydration, can complement dietary adjustments. For some, medications, supplements, or alternative therapies may provide relief from symptoms. 

Identifying sugar intolerance is the first step towards managing the condition effectively. At-home test kits such as those manufactured by Advance Food Intolerance Labs (AFIL) can be a convenient yet accurate tool to help identify sugar intolerance. By understanding the types of sugars that can cause intolerance, recognizing common symptoms, and considering genetic factors, you can gain valuable insights into your health.

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  4. Li, Chung-Hao, et al. "Long-term consumption of the sugar substitute sorbitol alters gut microbiome and induces glucose intolerance in mice." Life Sciences 305 (2022): 120770.

Author: Dr. Sony S. | Panel Expert, Medical Doctor Dr. Sony is known for her medical articles, written with in-depth detail and accuracy owing to her vast medical knowledge and thorough research of each article. She completed her degree with multiple scholarships from Guangzhou Medical University and is a board-certified Clinical Doctor. She is currently working as a Medical Officer in the emergency department of a renowned hospital and continues to publish numerous medical papers and articles. Dr. Sony continues to lead the way in medical breakthroughs, unparalleled by her high level of detail, knowledge and passion for discovering new sciences and innovative healthcare treatments.

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