The Effect of Probiotics on Lactose Intolerance
Condition: Lactose Intolerance
MeSH terms: Lactose Intolerance
Study type: Interventional

Summary: 
      Lactose intolerance (LI), also known as lactose malabsorption is the most common type of
      carbohydrate malabsorption. It is associated with the inability to digest lactose into its
      constituents, glucose and galactose, due to low levels of lactase enzyme activity (1-2). At
      birth, lactase activity is at the highest and it declines after weaning (1-2). The unabsorbed
      lactose is metabolized by colonic bacteria to produce gas (hydrogen (H2) and methane (CH4))
      and short chain fatty acids. Symptoms related to LI appear 30 minutes to 2 hours after
      consumption of food products containing lactose. Related symptoms include: bloating,
      cramping, flatulence and loose stool (1-2, 17-18).

      Highest rates of LI are found in the Asian populations, Native Americans and African
      Americans (60-100%), while lowest rates are found in people of northern European origin
      (including northern Americans) (3-4).

      The diagnosis of LI based on patients' symptoms is sometimes problematic, since these
      symptoms are not specific and may differ from one patient to another. Breath hydrogen test
      have been advocated as the best diagnostic tool for the assessment of LI (15-16). During the
      test, subjects are sampled for hydrogen levels of breath samples at base line and every 30
      minutes after the administration of 50 grams of oral lactose, for a total period of 180
      minutes. A breath sample with > 20 ppm above baseline is considered positive for LI (15-16).

      There are no established treatments for LI, other than almost complete avoidance of lactose
      rich dairy products. Avoidance of dairy products is a major concern since its outcome may
      result in a dietary calcium intake that is well below recommended dose of 1,000 mg per day
      for men and women and 1,300 mg for adolescents (8-10). For this reason different course of
      action needs to be considered instead of a complete exclusion of dairy products by LI
      patients.

      Two possible interventions in the case of LI are the supplement of commercially available
      lactase (tablets) or the addition of probiotics.

      The consumption of lactase enzyme as a food supplement may assist in restoring adequate
      levels of the enzyme needed for hydrolysis of lactose, especially for patients with low, or
      non existent levels of lactase. On the other hand, lactase products are problematic since not
      all lactase preparations are of the same concentration. Moreover, it is difficult to asses
      the amount of lactase tablets needed in order do fully hydrolyze lactose in each dairy mill
      (14).

      Probiotics are live microorganisms that are commonly used in order to prevent or treat a
      disease. The current definition by the Food and Drug Administration and the World Health
      Organization is "Live microorganisms which, when administered in adequate amounts, confer a
      health benefit on the host." These microorganisms are a heterogeneous group, they are
      nonpathogenic and produce beta- galactosidase or lactase intracellularly that may assist in
      the digestion of lactose (11).

      Studies have shown that people with lactose intolerance tolerated the lactose in yogurt
      better than the same amount of lactose in milk. The assumption was that the presence of
      lactase producing bacteria in the yogurt, especially Lactobacillus acidophilus, contributed
      to the digestion and absorption of lactose (5-6, 13).

      It was also found that the presence of Lactobacillus bulgaricus and Streptococcus
      thermophilus alleviate lactose intolerance through their ability to produce lactase enzyme
      (7).

      Finally, in another study it was found that consumption of milk containing Bifidobacterium
      longum resulted in significantly less hydrogen production and flatulence as compared to the
      consumption of control pasteurized milk (12).

      Based on the mentioned data, the investigators speculate that the administration of
      probiotics may assist with the consumption of dairy products containing lactose. Therefore,
      the aim of this study is to evaluate the effect of probiotics on patients with LI.
    

Detailed description: 
      lactose hydrogen breath test (LHBT) will be performed at base line and at each visit (total
      of 7 breath samples from each patient). All subjects will be presented for the lactose
      hydrogen breath test after 8 hours fast.

      At the initial stage, the subjects will take a base reading at time 0.

      Subjects will then receive 50 g of lactose dissolved in a 100 ml of plain water and will
      perform further breath test samples every 30 minutes for 3 h. All breath samples will be
      end-expiratory and analyzed immediately by a Portable Breath Hydrogen Monitor (Gastro+
      gastrolyzer, Bedfont Instruments, Holywell Lane, Upchurch, Kent, England). The concentration
      of breath hydrogen will be measured in parts per million (ppm). The measurements will then be
      plotted graphically and analyzed. The effect of probiotics on LI treatment will be measured
      by the following criteria:

        1. If hydrogen levels measured after 6 months of treatment will be lower than levels
           measured at time 0 and/or patients will report a decrease of symptoms, the treatment of
           LI with Probiotics will be considered successful.

        2. If hydrogen levels measured after 6 months of treatment will be the same or higher than
           levels measured at time 0 and/or patients will report an unchanged state or an increase
           of symptoms, the treatment of LI with probiotics will be considered unsuccessful.
    

Intervention name(s): Bio-25
Intervention type(s): Dietary Supplement
Intervention description(s): Bio-25 is an innovative formula containing 11 different strains of unique probiotic bacteria and over 25 billion active bacteria in each capsule. All participants will receive either Probiotics (Bio-25,will be provided by SupHerb) or placebo pills blindly for six months. One day prior to each visit, subjects will be asked to consume lactose, fructose and sorbitol free foods, in order to avoid high base line of hydrogen from the presence of unabsorbed carbohydrates. Subjects will also be asked not to smoke 24 hours prior to each visit.
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Supportive Care
Keywords: Probiotics; Lactose