It’s estimated that 75% of the world’s population lose the ability to completely digest lactose after infancy (1). Insufficient levels of lactase are often described as the cause of lactose intolerance, and therefore a common belief is that lactose intolerance is a permanent condition. However, scientific studies have made it clear that this is not the case, and it seems that lactose intolerance can actually be easily treated in most people! Some species of bacteria have lactose digesting enzymes, and when they get a chance to grow in the gut they can transfer their genes to the bacteria on the lining of the gut.
Lactic acid bacteria behave differently depending on the species and have varying effect in people with lactose intolerance (2).
One study showed that symptoms of lactose intolerance were alleviated significantly after supplementation with yoghurt and a probiotic capsule containing Bifidobacterium longum (3). Another similar study showed the same results and also concluded that the effect could persist for 3 months after suspension of probiotic consumption (4).
Dairy products act as a “delivery” system and strongly enhance the survival of probiotic bacteria into the gut (6,7). Eating fermented dairy products, such as yoghurt with live cultures, is one of the best strategies to get the needed bacteria. Kefir has also shown to improve lactose digestion and tolerance (5).
It’s important to eat small amounts of lactose while introducing lactose digesting bacteria from fermented dairy. Until the gut adjusts, symptoms of lactose intolerance will persist.
Pasteurized, fat-reduced and homogenized milk from sick animals isn’t healthy. Lactose intolerance is for some people a blessing in disguise (like gluten intolerance) if they eat healthier foods instead of pasteurized, fat-reduced milk. However, everyone should be able to choose for themselves and have the knowledge to treat lactose intolerance.
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2: Andrew Szilagyi. Prebiotics or probiotics for lactose intolerance: a question of adaptation
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3: Zhong Y, Huang CY, He T, et al. Effect of probiotics and yogurt on colonic microflora in subjects with lactose intolerance.
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4: Almeida CC, Lorena SL, Pavan CR, et al. Beneficial effects of long-term consumption of a probiotic combination of Lactobacillus casei Shirota and Bifidobacterium breve Yakult may persist after suspension of therapy in lactose-intolerant patients.
Nutr Clin Pract. 2012 Apr;27(2):247-51. Epub 2012 Mar 8.
5: Hertzler SR, Clancy SM. Kefir improves lactose digestion and tolerance in adults with lactose maldigestion.
J Am Diet Assoc. 2003 May;103(5):582-7.
6. Wang J, Zhong Z, Zhang W, et al. Comparative analysis of the gene expression profile of probiotic Lactobacillus casei Zhang with and without fermented milk as a vehicle during transit in a simulated gastrointestinal tract.
Res Microbiol. 2012 Apr 20. [Epub ahead of print]
7. Pitino I, Randazzo CL, Cross KL, et al. Survival of Lactobacillus rhamnosus strains inoculated in cheese matrix during simulated human digestion.
Food Microbiol. 2012 Aug;31(1):57-63. Epub 2012 Mar 3.
[…] and gluten sensitivity are often classified as permanent conditions, but the fact is that bacteria in the gut can provide the needed enzymes to break down lactose and are also able to degrade harmful gluten […]