Safety of probiotics

Probiotics (live bacteria) have been consumed safely via food for thousands of years. More recently, these bacteria have been isolated and selected for use in probiotic supplements and many of the bacterial species now have GRAS (generally recognised as safe) status.

Proven to be safe

A large number of clinical trials have been undertaken using probiotics for a wide range of diseases, with few associated adverse events. As a result, probiotics are generally assumed to be safe, although few systematic safety studies have been done with probiotic organisms, especially in vulnerable populations.[1] Most of the rare cases of infection with lactobacilli have occurred in patients with severe underlying conditions, although populations identified as potentially vulnerable include those with immune compromise, premature infants, patients with short bowel syndrome, those with central venous catheters and patients with cardiac valve disease.[1]

Probiotics generally regarded as safe

Whilst there are some theoretical adverse risks relating to the use of probiotics in humans, Lactobacilli, bifidobacteria and lactococci strains of probiotics are generally regarded as safe (GRAS).[2] Experts recommend that strains used for probiotics should be selected from the commensal flora of humans and should not carry intrinsic resistance to antibiotics as this would prevent treatment of a rare probiotic infection. They also state that responsible probiotics manufacturers have procedures for surveying adverse events caused by existing strains and for screening new strains. [3]

Safety of ProVen Probiotics

The Lab4 consortia of bacteria used in ProVen Probiotics were developed more than 15 years ago. Since then they have been studied in 10 clinical trials with a variety of populations, including pregnant women and newborn babies. As part of the Swansea Baby Trial [4] with pregnant mothers and their newborn infants, the safety of the probiotics was tracked and shown to be safe. The results of this safety study were reported and form part of the limited library of probiotics safety studies, particularly in this vulnerable population [5]. The Lab4 bacteria are also used in a wide range of products sold in very large numbers worldwide and are monitored for reporting of adverse events.

[1] Doron S & Snydman DR 2015 Risk and Safety of Probiotics Clin Infect Dis 60 (Suppl 2)
[2] Snydman DR 2008 The Safety of Probiotics Clin Infect Dis 46 (Suppl 2)
[3] Borriello SP et al 2003 Safety of Probiotics That Contain Lactobacilli or Bifidobacteria Clin Infect Dis 36:775-80

[4] Allen SJ et al 2014. Probiotics in the prevention of eczema: a randomised controlled trial. Archives of Disease in Childhood 99(11): 1014–1019

[5] Allen SJ et al 2010. Dietary supplementation with Lactobacilli and Bifidobacteria is well tolerated and not associated with adverse events during late pregnancy and early infancy. Journal of Nutrition 140:483-488

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Early immune system development - ProVen Probiotics

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