From ShortGut - Wiki
Prebiotics: Food for the good guys
Random facts from an ongoing study of this emerging field:
- This is a relatively new area: first major paper was in 1995. Doctors may not know much about it. Many studies just coming out in recent years (2000+).
- Prebiotics may be more important than probiotics for several reasons:
- Stomach acid neutralizes most bacteria (good or bad) before they can get to the intestine, so taking live bacteria orally is probably not very effective.
- Most of these gut bacteria are already there, and the main factor on their levels relative to other bacteria is how well they thrive. Feeding them is clearly a good idea.
- Main sources: FOS (fructo-oligosaccharides) -- long chain sugars that cannot be digested by us, and thus are left overs for the bacteria. Inulin is one particular source, derived from chickory root, which has longer-chains.
- Which is best source? Nothing definitive, but it looks like inulin might be better than FOS. General clinical studies seem to show FOS and Inulin produce similar results in terms of overall good bacteria growth, etc.
- This paper: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1265942&rendertype=abstract shows that "butyrate was the major fermentation product on inulin, whereas mostly acetate and lactate were produced on FOS." -- it seems that butyrate has a lot of good effects, so maybe Inulin is better? Even though many of the bacteria could not directly metabolize the Inulin, they were able to indirectly. The gut is a very complex environment with many many interactions between the bugs.. Amazing.
- The lactic acid produced by FOS, in large quantities, can inflame the intestine -- see discussion below about important cautionary results.
- Human breast milk is 1/3 oligosaccharides!! Over 130 different types are present. Recent studies are suggesting that this may be a critical factor in the benefits of breast milk. However, this may be for different reasons than prebiotic factors, although these oligosaccharides are not digested directly. Somehow they may have direct anti-microbial action and other benefits? Not sure why prebiotic function can be excluded.
Short gut specific
- Kanamori Et Al, 2001: http://www.springerlink.com/content/u4x6q448rq0407u6/ KanamoriEtAl01.pdf -- synbiotics case report, showing good benefits. Dose of prebiotics was 3g/day (oligomate HR -- seems to be only used by this research group). Kanamori et al have several other similar papers.
- Recent review of bacterial overgrowth that likely reflects standard wisdom among practicing doctors -- give people antibiotics, and maybe there is something to prebiotics, but it hasn't been studied in these populations, and who knows but it might do some good:
- http://www.jpgn.org/pt/re/jpgn/fulltext.00005176-200203000-00014.htm -- recent review.
- http://jn.nutrition.org/cgi/content/full/136/8/2270 -- reply to review, with important counterpoints suggesting some caution in use of FOS.
- http://jn.nutrition.org/cgi/content/full/136/1/70 BruggencateEtal06.pdf -- important cautionary results showing increase in gut permeability with very high levels of FOS intake (20g / day). These results should be taken with appropriate contextualization: the FOS intake levels are way above normal supplement levels (which are at most 5g/day), and the bad effects were only present with very low levels of calcium. So, the key lessons are that too much of a good thing is bad, and it is very important to keep calcium levels up!! Also, these results seem to be caused by lactic acid production, which irritates the intestine. Perhaps combined with the other results on Inulin vs. FOS, suggesting that lactic acid is produced more by FOS, this suggests that Inulin might be better.
- http://www.ncbi.nlm.nih.gov/sites/entrez?db=PubMed&cmd=Retrieve&list_uids=15877897 -- pediatric study showing good effects (also has dosing levels: .4 to 1 g/dL of formula).
Commercial Sources of Supplements
- Fancy blend: http://www.protherainc.com/prod/proddetail.asp?id=K-BTGC
- Inulin: http://www.nowfoods.com/index.php?action=itemdetail&item_id=3858 (available at Vitamin Cottage stores, and maybe Whole Foods or Wild Oats.
- FOS: http://www.nowfoods.com/?action=itemdetail&item_id=3370 (avail at Boulder Whole Foods, but not Inulin)
Informal List of Results -- Add Yours Here!
- We use inulin (added to formula) and have not needed antibiotics for bacterial overgrowth.
- Per Dr. Kocoshis at Cincinnati, fiber products such as Benefiber and Metamucil are themselves prebiotics