First thing about soil based organisms, there has been some evidence that if you don't have a healthy gut flora already (more good bacteria than bad) soil based probiotics may do more damage and possibly become pathogenic. If you're just starting with a probiotic regimen and have had an arguably unhealthy diet in the past recommend steering clear of these in the beginning simply from the perspective of risk/reward, go more toward the lactic acid probiotics. When you've done a regiment of lactic acid probiotics, not been on antibiotics, and eating a relatively clean diet soil based organisms may have even more benefits than the lactic acid based probiotics.
Strains
Bifidobacteria and Lactobacilli (most studied strain families): treatment/improving allergies, lactose intolerance, eczema, acne, improved digestive health
Immune System Support: Bifidobacterium lactis HN019, Lactobacillus reuteri ATCC55730, Lactobacillus rhamnosus GG, Lactobacillus, Bifidobacterium lactis Bb-12
Treatment for Diarrhea: S. cerevisiae (S. boulardii), Lactobacillus rhamnosus GG (LGG), Lactobacillus casei DN-114 001, Lactobacillus acidophilus CL1285 plus Lactobicillus casei Lbc80r
References:
- http://www.ncbi.nlm.nih.gov/pubmed/15106189
- http://www.ncbi.nlm.nih.gov/pubmed/19584499
- http://www.ncbi.nlm.nih.gov/pubmed/16313688
- http://www.ncbi.nlm.nih.gov/pubmed/16126048
- http://www.ncbi.nlm.nih.gov/pubmed/23474283
- http://www.ncbi.nlm.nih.gov/pubmed?cmd=Link&dbFrom=PubMed&from_uid=21352578&holding=f1000%2Cf1000m%2Cisrctn
- http://www.ncbi.nlm.nih.gov/pubmed?term=Probiotics
- http://nccam.nih.gov/health/probiotics/introduction.htm
- http://newsroom.ucla.edu/portal/ucla/changing-gut-bacteria-through-245617.aspx
- http://www.health.harvard.edu/fhg/updates/update0905c.shtml
- http://cid.oxfordjournals.org/content/46/Supplement_2/S96.full
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