Lactose Intolerance
What is lactose intolerance?
Lactose intolerance is the inability to digest significant amounts of lactose, the predominant sugar found in milk. This inability results from a shortage of the enzyme lactase, which is normally produced by the cells that line the small intestine. Lactase breaks down milk sugar into simpler forms that can then be absorbed into the bloodstream. When there is not enough lactase to digest the amount of lactose consumed, the results, although not usually dangerous, may be very distressing. While not all people deficient in lactase have symptoms, those who do are said to be lactose intolerant. Common symptoms include nausea, cramps, bloating, wind, and diarrhoea, which begin about 30 minutes to two hours after eating or drinking foods containing lactose. The severity of symptoms varies according to the amount of lactose each individual can tolerate.
It is thought that 15-30% of Europeans may have a relative deficiency of lactase called adult-acquired hypolactasia. This may follow surgery or injuries to the small intestine (eg Crohn’s disease), occur in patients with coeliac disease or develop naturally over time (after about the age of two years, the body begins to produce less lactase).
How Is lactose intolerance diagnosed?
The most common test for measuring absorption of lactose in the digestive system is the hydrogen breath test (see separate Patient Information sheet) that measures the amount of hydrogen in the breath. Normally, very little hydrogen is detectable in the breath. However, undigested lactose in the colon is fermented by bacteria, and various gases, including hydrogen, are produced. The hydrogen is absorbed from the intestines, carried through the bloodstream to the lungs, and exhaled. In the test, the patient drinks a lactose-loaded beverage, and the breath is analysed at regular intervals. Raised levels of hydrogen in the breath indicate improper breakdown or digestion of lactose. This test is available in Tunbridge Wells (contact@westkentgastroenterology.com or 01892740374 for more information).
How is lactose intolerance treated?
Fortunately, lactose intolerance is relatively easy to treat. There is no treatment to improve the body's ability to produce lactase, but symptoms can be controlled through diet. Individuals differ in the amounts of lactose they can handle. For example, one person may suffer symptoms after drinking a small glass of milk, while another can drink one glass but not two. Others may be able to manage ice cream and aged cheeses, such as cheddar, but not other dairy products. Lactose-reduced milk and other products are available at many supermarkets. Expert advice about lactose-containing foods may be sought from a dietician.
Please get in contact with me if further information is required either via e mail (info@westkentgastroenterology.com) or by phone (01892 740374).