Understanding Lactose: IBS Awareness Month 2018, Week 2

Our Week 2 FODMAP Focus is the ‘D’ in FODMAP!

Join us for week 2 as we launch into learning all about lactose, the ‘D’ in the FODMAP acronym below!

Understanding lactose & lactose intolerance – The beginner’s guide

Lactose intolerance and IBS

People with Irritable Bowel Syndrome (IBS) often have heightened sensitivity to the effect of lactose intolerance in the gut compared to individuals without IBS. Studies have found that lactose intolerance affects 24-45% of IBS patients.¹ Please also be noted that individuals can have lactose intolerance without IBS.

No matter you have IBS or lactose intolerance alone, please continue reading!

What is lactose? What is lactose intolerance?  

Lactose is the main carbohydrate found in milk and other dairy products. When you consume food or drinks containing lactose, an enzyme named lactase in the small bowel will break down lactose into smaller constituents for digestion and absorption.^2,3 However, some people might produce less lactase than the others.

If the small bowel has insufficient lactase, the lactose consumed will not be digested properly and will continue through to the large bowel. Lactose in the large bowel will be fermented by the gut bacteria, which produces gases including hydrogen, carbon dioxide and methane. This gas production not only can lead to unpleasant gastro-intestinal symptoms such as distention, bloating, flatulence and constipation but can also draw water into the large bowel resulting in loose stools or diarrhoea.^2,3

To diagnose lactose intolerance, the hydrogen breath test is a simple, non-invasive and reliable investigation test.³ Lactose intolerance is indicated when hydrogen and methane levels of breath meet a certain criteria following the oral consumption of standard dose of lactose.⁴

Another way to diagnose lactose intolerance is an elimination diet which involves removing lactose in the diet and assessing whether symptoms improve, followed by a re-introduction of lactose in the diet to assess whether symptoms return.

Who’s affected by lactose intolerance?

The prevalence of lactose intolerance varies across populations.

East Asian (90-100%), Indigenous North Americans (80-100%), Central Asian (80%), African Americans (75%), African (70-90%) have a higher likelihood of having lactose intolerance.^1,5-8 Caucasians have a lower incidence, with French (17%), Austrian (15-20%), German (15%) and British (5-15%) having the lowest rates.^1,5-8

The ‘D’

FODMAPs are the groups of carbohydrates which are poorly absorbed in our gut. The ‘D’ in ‘FODMAP’ stands for disaccharide which is formed by two linked simple sugars. Lactose is a type of disaccharide composed of glucose and galactose.³ As previously stated, some people malabsorb this carbohydrate due to insufficient lactase.

If you are lactose intolerant, should all dairy products be avoided? What about low FODMAP products?

If you have lactose intolerance or IBS issues particularly related lactose, you won’t need to completely avoid dairy!

Recent research has suggested that most people with lactose intolerance can consume up to 12 to 15g of lactose without any symptoms.⁹ Low FODMAP products are low lactose too (as mentioned ‘D’ refers to lactose).

The following table lists the lactose content of some commonly consumed dairy foods:¹⁰

^Depends on individual intolerance. *According to the Australian Dietary Guidelines, people with lactose intolerance can tolerate up to 250ml of milk each day if it is consumed in small amounts throughout the day and consumed with other foods.

Liddells Lactose Free, The Nutty Milk Company & Green Valley Organics Lactose Free

Low FODMAP dairy products and nut milk alternatives Certified by FODMAP Friendly are also your go-to choices!

Liddells and Green Valley Organics add lactase into their products, which breaks down the lactose in milk. Have a look at the lactose free mechanism below:

When an enzyme called ‘lactase’ is added to dairy products, it splits lactose molecules found in milk and milk products into their smaller components; monosacchardies called glucose & galactose. Glucose & galactose are not FODMAPs, therefore they are safe to consume while following a low FODMAP diet.

 The Nutty Milk Company make nut-based dairy-free alternatives, great lactose-free options if you’re vegan and following a low FODMAP diet.

Check out the Liddells range below:

The Nutty Milk Company

If you like nut milk, The Nutty Milk Company’s products are also tested and certified FODMAP Friendly! Check out Almond, Chem-free Almond, Cashew and Macadamia Milks which are available to be purchased online or from a list of retail stores.

If you are in the U.S., good news for you too! Many Green Valley Organics Lactose Free dairy products have also been tested and certified FODMAP Friendly.

Look out for Green Valley‘s big range of kefirs, whole milk & low fat yoghurts, cheeses and butter. Just like Liddells, these products are not only low in lactose, but are low in all the FODMAPs.

You can buy these products from leading American retailers and online stores across the USA:

All products shown here on this blog have been independently tested and proven low FODMAP. This means that they are low in all FODMAPs in the FODMAP acronym, including lactose, fructans, GOS, excess fructose and the sugar alcohols.

If you want to learn more about how we test foods for FODMAPs, click here.

Enjoy FODMAP Friendly Certified lactose free dairy and nut milks..

With Confidence!

Written by: Flora Cheung (APD, AN)

Edited by: Atlanta Miall-Shorten, (APD, AN, AccSD)

References

1. Lomer MC, Parkes GC, Sanderson JD. Review article: lactose intolerance in clinical practice – myths and realities. Aliment Pharmacol Ther [Internet]. 2008 [cited 2018 Mar 29];27(2):93-103. Available from: https://www.ncbi.nlm.nih.gov/pubmed/17956597
2. Yang J, Deng Y, Chu H, Cong Y, Zhao J, Pohl D, et al. Prevalence and Presentation of Lactose Intolerance and Effects on Dairy Product Intake in Healthy Subjects and Patients With Irritable Bowel Syndrome. Clin Gastroenterol Hepatol [Internet]. 2013 [cited 2018 Mar 29];11(3):262-268. Available from: https://www.ncbi.nlm.nih.gov/pubmed/23246646 doi: 10.1016/j.cgh.2012.11.034.
3. Pereira PC. Milk nutritional composition and its role in human health. Nutrition [Internet]. 2014;30(6):619-27. Available from: https://www.ncbi.nlm.nih.gov/pubmed/24800664 doi: 10.1016/j.nut.2013.10.011.
4. Shaw AD, Davies GJ. Lactose intolerance: problems in diagnosis and treatment. J Clin Gastroenterol [Internet]. 1999;28:208–16. Available from: https://www.ncbi.nlm.nih.gov/pubmed/10192605
5. De Vrese M, Stegelmann A, Richter B, Fenselau S, Laue C, Schrezenmeir J. Probiotics–compensation for lactase insufficiency. Am J Clin Nutr. 2001 Feb;73(2 Suppl):421S-429S.
6. Scrimshaw NS, Murray EB. The acceptability of milk and milk products in populations with a high prevalence of lactose intolerance. Am J Clin Nutr. 1988 Oct;48(4 Suppl):1079-159.
7. S. National Institute of Child Health and Human Development (NICHD). Lactose Intolerance: Information for Health Care Providers [Internet]. U.S.: NICHD Information Resource Centre; 2006 [cited 2018 Mar 29]. Available from: https://www1.nichd.nih.gov/publications/pubs/documents/NICHD_MM_Lactose_FS_rev.pdf
8. S. National Library of Medicine. Lactose Intolerance [Internet]. U.S.: NLM; 2018 [cited 2018 Mar 29]. Available from: https://ghr.nlm.nih.gov/condition/lactose-intolerance#statistics
9. Shaukat A, Levitt MD, Taylor BC, MacDonald R, Shamliyan TA, Kane RL, et al. Systematic review: effective management strategies for lactose intolerance. Ann Intern Med [Internet]. 2010 [cited 2018 Mar 29]; 152(12):797-803. Available from: https://www.ncbi.nlm.nih.gov/pubmed/20404262 doi: 10.7326/0003-4819-152-12-201006150-00241
10. Dairy Australia. Lactose Intolerance [Internet]. Australia: Nutrition Australia; 2011 [cited 2018 Mar 29]. Available from: https://www.nutritionaustralia.org/national/resource/lactose-intolerance