Lack of effect of lactose digestion status on baseline fecal micoflora.
BACKGROUND
The genetics of intestinal lactase divide the world's population into two phenotypes: the ability (a dominant trait) or inability (a recessive trait) to digest lactose. A prebiotic effect of lactose may impact the colonic flora of these phenotypes differently.


OBJECTIVE
To detect and evaluate the effects of lactose on subjects divided according to their ability to digest lactose.


METHODS
A total of 57 healthy maldigesters (n=30) and digesters (n=27) completed diet questionnaires, genetic and breath hydrogen testing, and quantitative stool analysis for species of bacteria. Log10 transformation of bacterial counts was compared with lactose intake in both groups using multiple regression analysis.


RESULTS
There was a significant relationship between genetic and breath hydrogen tests. Daily lactose intake was marginally lower in lactose maldigesters (median [interquartile range] 12.2 g [31 g] versus 15 g [29.6 g], respectively). There was no relationship between lactose intake and breath hydrogen tests in either group. There were no differences in bacterial counts between the two groups, nor was there a relationship between bacterial counts and lactose intake in either group.


CONCLUSIONS
The differential bacterial effects of lactose were not quantitatively detected in stool samples taken in the present study.
Szilagyi
Andrew
A
Division of Gastroenterology, Department of Medicine, Sir Mortimer B Davis Jewish General Hospital, McGill University School of Medicine, Montreal, Canada. aszilagy@gas.jgh.mcgill.ca
Shrier
Ian
I
Chong
George
G
Je
Jung Sung
JS
Park
Sunghoon
S
Heilpern
Debra
D
Lalonde
Catherine
C
Cote
Louis-Francois
LF
Lee
Byong
B
D000328:Adult; D001644:Bifidobacterium / Q000254:growth & development / Q000302:isolation & purification; D001944:Breath Tests; D015169:Colony Count, Microbial; D003430:Cross-Sectional Studies; D004040:Dietary Carbohydrates / Q000009:adverse effects / Q000378:metabolism; D004063:Digestion / Q000235:genetics*; D005243:Feces / Q000382:microbiology*; D005260:Female; D041981:Gastrointestinal Tract / Q000378:metabolism / Q000382:microbiology; D020022:Genetic Predisposition to Disease; D006801:Humans; D043322:Lactase / Q000235:genetics / Q000378:metabolism; D007778:Lactobacillus / Q000254:growth & development / Q000302:isolation & purification; D007785:Lactose / Q000009:adverse effects / Q000235:genetics / Q000378:metabolism; D007787:Lactose Intolerance / Q000235:genetics / Q000382:microbiology; D008297:Male; D010641:Phenotype; D056692:Prebiotics; D011795:Surveys and Questionnaires
D004040:Dietary Carbohydrates; D056692:Prebiotics; D043322:Lactase; D007785:Lactose