Science and SCD

Ok, ok!  Just one more post on the Specific Carbohydrate Diet and then I will (temporarily) shut up about it.  It’s all residual excitement over that pediatric clinical trial from last week.  I feel like that was the first major leak in the mainstream medical dike…

As promised, I want to run through a little of the science supporting the use of SCD in traditional IBD, autistic enterocolitis, SIBO (small intestine bacterial overgrowth), etc.

Firstly, we have known for many, many years that sugar is a problem.  For example, in 1997, an article (“Pre-illness dietary factors in Inflammatory Bowel Disease”)[i] appeared in the journal Gut, which is a pretty  major one in the field, which states that, “A high sucrose consumption was associated with an increased risk for IBD against population controls…Fructose intake was negatively associated with risk for IBD.”  That is, a di-saccharide is bad.  A mono-saccharide is good.

One of my favorite articles is from the Israeli Medical Association Journal in 2000, “Carbohydrate Malabsorption and the Effect of Dietary Restriction on Symptoms of Irritable Bowel Syndrome and Functional Bowel Complaints.”[ii]  These researchers found that, “Combined sugar malabsorption patterns are common in functional bowel disorders and may contribute to symptomatology in most patients.  Dietary restriction of the offending sugar(s) should be implemented before the institution of drug therapy.”  (I’ve added the underline because – well, how about that “before drug therapy” bit?!)

The list of pertinent research goes on and on, and I do recognize that not everyone shares my penchant for reading scientific literature late on Friday nights, so I’ll wrap up with just three more articles that you should know about.

Firstly, in 2010, an article[iii] came out in the journal Nutrition which had me beside myself the day I read it.  For the past 6 years, I’ve affectionately called it the, “What do we really know about SIBO?” article.  The authors explain that it’s actually very hard to accurately test for small intestine bacterial overgrowth, so the best course of action is to treat for it when it’s suspected – and if the person gets better, that’s what they had.  And how to treat? Well, the answer, as it turned out, was to do exactly what I had been doing with my nutrition clients for years:   probiotics, prebiotics (fiber that feeds good bacteria), sending them to their doctors to discuss gut antibiotics (when absolutely necessary), and…a diet low in foods that ferment….which is the definition of SCD.

Then, in 2011 a study[iv] was done at the University of California at Davis, which was presented at the 15th International Congress of Mucosal Immunology in Paris.  (I wish I had been there…in Paris…in July…learning about intestinal mucosa….)  Researchers compared the effects of a Low Residue Diet (don’t worry about what this is as it’s not important) to SCD on the microbiota in people with Crohn’s Disease.  The study was very small (only 6 people), but it was a double blind, randomized, cross-over study, so the pinnacle of clinical trials.  Controls were healthy people from the same geographic location.  They found that the Low Residue Diet resulted in further depletion of the microbiome while SCD led to a dramatic increase in microbial diversity.

They conclude that, “… diet changes in patients with Crohn’s appear to result in dramatic changes in the large intestinal microbiome and will need to be investigated further with a larger number of subjects.”

Finally, a truly seminal paper as far as I’m concerned, dating from 2011, “Impaired Carbohydrate Digestion and Transport and Mucosal Dysbiosis in the Intestines of Children with Autism and Gastrointestinal Disturbances,”[v] which truly rocked my world.  This one is pretty complex, so I won’t go into details.  What you need to know is that these researchers found huge amounts of undigested carbohydrates sitting around in the guts of kids with autism (with GI issues), and subsequent, huge excesses of bacterial overgrowth.

Hmmm.  Seems like Elaine Gottschall had this all pretty well sussed out.  Remove the fermentable complex carbohydrates, leading to an improved the gut biome, and you can effectively treat bowel disease.


[i] Reif, S, Klein, I, Lubin, F, Farbstein, M, Hallak, A, Gilat, T. Pre-illness dietary factors in inflammatory bowel disease.  Gut: 1997 Jun; 40(6): 754-760.

[ii] Goldstein, R, Braverman, D, Stankiewicz, H.  Carbohydrate malabsorption and the effect of dietary restriction on symptoms of irritable bowel syndrome and functional bowel complaints.  Israeli Medical Association Journal, 2000 Aug;2(8):583-7.

[iii] Gibson, PR, Barrett, JS.  The concept of small intestine bacterial overgrowth in relation to functional gastrointestinal disorders.  Nutrition, 2010 Nov-Dec;26(11-120:1038-43.

[iv] J. Antonio Quiros, Sumathi Sankaran, Jimmy Pan, Matthew Rolston, Jay Li, Steven Bauman, Gary L. Andersen, Todd Z. DeSantis, Thomas Prindiville, and Satya Dandekar.  Impact of diet in fecal microbial diversity in patients with Crohn’s Disease.  presented at The 15th International Congress of Mucosal Immunology (ICMI 2011) in Paris, France in July 2011.

[v] Williams, BL, Hornig, M, Buie, T, Bauman, ML, Cho Paik, M, Wick, I, Bennett, A, Jabado, O, Hirschberg, DL, Lipkin, Wi.  Impaired Carbohydrate Digestion and Transport and Mucosal Dysbiosis in the Intestines of Children with Autism and Gastrointestinal Disturbances. PLoS One: 2011;6(9).

One Comment on “Science and SCD

  1. Pingback: What Do We Really Know About Treating SIBO – THE BIOME BUZZ

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