Lactose intolerance

Lactose intolerance is a condition in which the digestive system is unable to break down lactose, a disaccharide (sugar) found in dairy products such as milk, yoghurt, custard and ice cream, and in smaller amounts in butter, cheese and cream.

Because the lactose is not digested, it passes into the large intestine intact where normal gut bacteria ferment this sugar. Fermentation causes a build-up of gas in the lower intestine, which can lead to a range of gastrointestinal symptoms including stomach cramps, bloating and flatulence.

The extent of lactose intolerance varies greatly from person to person, so the severity of symptoms can vary.

Diagnosis

Gastrointestinal symptoms can be associated with food allergies, food intolerances and a range of other short and long term medical conditions, and managing the symptoms without knowing the cause can be frustrating. The good news is that there are several ways to diagnose lactose intolerance:

• Biopsies can be performed to observe the intestines, however this is an invasive procedure.
• A large lactose dose can be consumed and gastrointestinal symptoms observed over the following 30 minutes to 2 hours to see whether the symptoms are consistent with known lactose intolerance symptoms.
• Hydrogen breath testing. Normally there is very little hydrogen present in the breath, however when a person is lactose intolerant, hydrogen levels in the breath increase after eating a lactose-containing product. Hydrogen breath testing involves a lactose challenge followed by measuring the breath over a three hour period to detect any hydrogen peaks. Food & Nutrition Australia now offer this type of Lactose Intolerance Testing in our clinic.

Managing lactose intolerance

People with lactose intolerance generally need to avoid or reduce their intake of lactose containing foods. Label reading skills are essential as milk products are used in a large variety of processed foods. Another option is to take lactase enzyme tablets, which break down lactose in foods.

For more information or to book an appointment, contact an FNA Accredited Pracitising Dietitian.

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