Do you think you have an issue with lactose? Or maybe you have IBS? Well today I am going to talk about Lactose Malabsorption, Lactose Intolerance, Dairy Foods and their lactose content as well as the Low FODMAP Diet and how they all tie in, so stay tuned!
What is it?
Lactase is an intestinal enzyme required to cleave lactose into its readily absorbable monosaccharides glucose and galactose .Lactose Intolerance occurs when there is a lactase deficiency or the activity of the lactase enzyme is suppressed for whatever reason, resulting in the malabsorption of lactose which is subsequently fermented by colonic bacteria producing gas. The presence of this gas can result in numerous symptoms including: stomach pain, bloating, flatulence, constipation and diarrhoea. If symptoms are experienced then it is considered to be lactose intolerance if gas is detected via a hydrogen-methane breath test but no symptoms are experienced then it is considered to be lactose malabsorption .
Lactose Malabsorption and Intolerance prevalence ranges considerably between ethnic groups with prevalence in Caucasian populations below 10% and up to over 90% in Asian populations .
The breath test is considered to be the preferred method for assessing these conditions due to being relatively inexpensive and non-invasive. Research has shown that the Hydrogen and Methane breath test for Lactose Malabsorption and Intolerance has the highest accuracy of any of the breath tests when compared to genetic testing with sensitivity and specificity ranging from 76%-94% ,77%-96%, respectively . In saying this false positive result can still occur. Typically, a false result can occur in the presence of small intestinal bacterial overgrowth (SIBO) . Consequently, a lactulose breath test must be completed as a control test at least 2 days before the lactose test to not only indicate the primary gas produced when malabsorption is occurring but also give an indication of oro-caecal transit time and indicate the possible presence of SIBO . If SIBO is considered a possibility then a glucose breath test will be administered to confirm the presence of proximal bowel bacterial overgrowth. To find out more about breath testing and SIBO check out two of my previous blogs.
There is a bit of confusion at the minute about whether lactose and dairy products should be eliminated during the elimination part of the Low FODMAP Diet due to recent research highlighting the benefit of small but regular intakes of dairy throughout the day to help your tolerance of lactose . If you have been medically diagnosed with IBS or have been suggested to follow a Low FODMAP Diet by your dietitian, then I would suggest that you also eliminate lactose. Eliminating lactose does not mean, however, that you must eliminate all dairy products. For example, take a look at this table from Nutrition Australia assessing the lactose content of dairy foods http://www.nutritionaustralia.org/sites/default/files/Lactose%20Intolerance_0.pdf
You can see that hard cheeses, brie and butter contain minimal amounts of lactose and would be acceptable on a Low FODMAP Diet. Most of the dairy foods that are high in lactose also come in lactose free varieties, allowing you to still consume them and maintain your calcium intake.
You should aim to reintroduce lactose back into your diet with your dietitian to determine your individual tolerance level.
I hope that this post gives you a little more insight into lactose and lactose intolerance and where it fits in the Low FODMAP Diet.
Next week I will be posting my Lactose Free Barney Banana recipe so stay tuned!! If you can’t wait for some lactose free ice-cream then check out one of my previous blogs on how to make delicious Chocolate Lactose Free Ice-cream.
Until Next Time,
I am Atlanta Miall,
 Yang JF, Fox M, Chu H, Zheng X, Long YQ, Pohl D, et al. Four-sample lactose hydrogen breath test for diagnosis of lactose malabsorption in irritable bowel syndrome patients with diarrhoea. World J Gastroenterol. 2015 Jun 28; 21(24): 7563-7570.
 Arola H. Diagnosis of hypolactasia and lactose malabsorption. Scand J Gatroenterol Soppl. 1994; 202:26-35.
 Nucera G, Gabriella M, Lupascu A, et al. Abnormal breath tests to lactose, fructose and sorbitol in irratable bowel syndrome may be explained by small intestinal bacterial overgrowth. Aliment Pharmacol Ther. 2005; 21:1391-1395.
 Bate JP, Irving PM, Barrett JS, Gibson PR. Benefits of breath hydrogen testing after lactulose administration in analysing carbohydrate malabsorption. Eur. J. Gastroenterol. Hepatol. 2009; 00:000-000.
 Suarez FL, Savaiano D, Arbisi P, Levitt MD. Tolerance to the daily ingestion of two cups of milk by individuals claiming lactose intolerance. The American journal of clinical nutrition. 1997; 65(5):1502-6.