Common Symptoms of a Fructose Intolerance

Fructose intolerance is a condition that impairs a person’s ability to comfortably digest:

• Fructose
• Fructans
• FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols)

These compounds are naturally present in many fruits and vegetables. They may also be found in processed foods containing ingredients like high fructose corn syrup, which is commonly used in commercial food products.

Because fructose intolerance is not widely discussed, researchers believe it is often mistaken for other digestive conditions. One study suggested that as many as one-third of people diagnosed with irritable bowel syndrome (IBS) may actually have misdiagnosed fructose intolerance.

If you experience digestive discomfort after eating fruit, it may be helpful to understand the two primary forms of fructose intolerance: dietary fructose intolerance and hereditary fructose intolerance.

Dietary Fructose Intolerance

Dietary fructose intolerance, also known as fructose malabsorption, is the most common form of fructose intolerance. It occurs when the intestines are unable to properly absorb fructose, the natural sugar found in fruit.

Common symptoms of dietary fructose intolerance include:

• Flatulence
• Bloating or abdominal swelling
• Abdominal pain
• Diarrhea and digestive discomfort

Because these symptoms overlap with symptoms commonly associated with conditions like IBS, many cases of fructose intolerance may go undiagnosed.

Fortunately, dietary fructose intolerance rarely causes serious long-term health complications. With dietary modifications and support from a healthcare provider, many people can successfully manage symptoms and maintain a healthy lifestyle.

Hereditary Fructose Intolerance

Hereditary fructose intolerance is a more serious inherited condition caused by a genetic mutation. People with hereditary fructose intolerance either do not produce enough aldolase B enzyme—or produce enzymes that do not function properly—which prevents the body from breaking down fructose effectively.

Hereditary fructose intolerance is rare, affecting approximately 1 in every 20,000 to 30,000 people. Symptoms often appear during infancy or childhood after exposure to fruit or fructose-containing foods.

Untreated hereditary fructose intolerance may lead to:

• Hypoglycemia (low blood sugar)
• Nausea and vomiting
• Abdominal pain
• Difficulty gaining weight
• Impaired growth and development
• Liver or kidney damage
• Organ failure
• Seizures

In severe cases, untreated hereditary fructose intolerance can be life-threatening. If an infant experiences an adverse reaction after consuming fruit or fructose-containing products, it’s important to seek immediate medical evaluation from a healthcare provider.

Healthcare providers may use several methods to help diagnose intestinal fructose intolerance:

• Fructose breath tests – These tests measure the amount of hydrogen and methane in a person’s breath after consuming a fructose-containing solution. Elevated levels may indicate fructose malabsorption. In some cases, individuals may benefit from following a low-fructose diet to help minimize symptoms.
• Elimination diets – If symptoms are not severe or urgent, healthcare providers may recommend an elimination diet to help identify possible trigger foods. During an elimination diet, certain foods and ingredients are temporarily removed and later reintroduced while monitoring symptoms. This process may help identify potential food sensitivities, including fructose malabsorption.

The most effective starting point for managing fructose intolerance is learning which foods contain high amounts of fructose so you can more easily avoid potential triggers.

Foods commonly high in fructose include:

• Fresh, sugary fruits like grapes, apples, and ripe bananas
• Dried fruit or fruit canned in syrup
• Certain vegetables, including broccoli, onions, and red peppers
• Wheat-based foods like bread, pasta, and pastries
• Sweeteners such as honey and high-fructose corn syrup
• Highly processed sweets
• Sodas sweetened with fructose

In some cases, a healthcare provider may also recommend following a Low FODMAP diet. This eating approach helps reduce exposure to short-chain carbohydrates commonly found in high FODMAP foods, which may contribute to digestive symptoms.

If you’ve been diagnosed with fructose intolerance, limiting or eliminating fructose-containing foods may help reduce symptoms. However, some people may still tolerate certain low-fructose fruits in moderation with guidance from a healthcare provider.

Examples of fruits that may be better tolerated in small amounts include:

• Citrus fruits like lemons, limes, and oranges
• Pineapple
• Certain melons, such as cantaloupe
• Certain berries, including strawberries
• Avocados

It’s also important to find alternative ways to obtain nutrients commonly found in fruits and vegetables. A multivitamin may help support nutritional balance by providing essential vitamins and minerals.

Many people struggle with digestive discomfort, but discerning the root cause isn’t always clear. With Everlywell, you can screen for everything from a food sensitivity to celiac disease affordably, conveniently, and with complete privacy protection. Find out more of what you can discover about your health by checking in with Everlywell today.