The simple answer is No.
Based on available studies and on the variety and microbiotic characteristics of strains used, it is difficult to clearly establish the necessary daily dose required when taking Microbiotics. For the past 20 years, in North America, most Microbiotics products have been marketed with a minimum of 1 Billion micro-organisms per dose with various concentrations going as high as 50 Billion per dose. Moreover, it has been reported that numerous studies in humans suggest that lactic acid bacteria at a level 1 to 100 Billion per day can decrease the incidence, duration and severity of gastric and intestinal illnesses.
An In vivo clinical study done on new-born infants (0-8 weeks) with orally administered bifidobacteria and lactobacilli at daily dosage of 9 Billion showed no side effects. Another study carried out on 100 children aged from 6 to 60 months with a mix of B. infantis and L. acidophilus at a daily dose of 6 Billion bacteria (i.e.: one capsule of 2 Billion micro-organisms tid) concluded that oral bacterial therapy was an effective adjuvant therapy in rotavirus positive and negative children with diarrhea and could safely be administered during an episode of acute diarrhea. Finally, two other clinical studies done with a highly concentrated probiotic formula (4 strains of lactobacilli, 3 strains of bifidobacteria and one strain of Streptococcus thermophilus) with daily dosages of 450 Billion and 3000 Billion were also well tolerated by all patients involved in these studies. ,
Based on this data and considering that the human’s natural intestinal flora is composed of over 400 species of bacteria and contains over 100 000 Billion micro-organisms, there is no risk in taking highly concentrated probiotics. As far as the minimum daily dose is concerned, based on our knowledge, the minimum recommended dose for adults should be 5 Billion while 1 Billion would be recommended for children.
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