title: Lactose intolerance: lack of evidence for short stature or vitamin D deficiency in prepubertal children.
abstract: BACKGROUND
  The health consequences of lactose intolerance (LI) are unclear.
  
  
  OBJECTIVE
  To investigate the effects of LI on stature and vitamin D status.
  
  
  OBJECTIVE
  LI subjects will have similar heights and vitamin D status as controls.
  
  
  METHODS
  Prepubertal children of ages 3-12 years with LI (n=38, age 8.61 ± 3.08y, male/female 19/19) were compared to healthy, age- and gender-matched controls (n=49, age 7.95±2.64, male/female 28/21).
  
  
  METHODS
  prepubertal status (boys: testicular volume <3cc; girls: Tanner 1 breasts), diagnosis of LI by hydrogen breath test, and no history of calcium or vitamin D supplementation. Vitamin D deficiency was defined as 25-hydroxyvitamin D [25(OH)D] <50 nmol/L. Gender-adjusted midparental target height (MPTH) z-score was calculated using NCHS data for 18 year-old adults. Data were expressed as mean ± SD.
  
  
  RESULTS
  There was no significant difference in 25(OH)D between the LI and non-LI subjects (60.1±21.1, vs. 65.4 ± 26.1 nmol/L, p = 0.29). Upon stratification into normal weight (BMI <85(th) percentile) vs. overweight/obese (BMI ≥85(th) percentile), the normal weight controls had significantly higher 25(OH)D level than both the normal weight LI children (78.3 ± 32.6 vs. 62.9 ± 23.2, p = 0.025), and the overweight/obese LI children (78.3±32.6 vs. 55.3±16.5, p = 0.004). Secondly, there was no overall difference in height z-score between the LI children and controls. The normal weight LI patients had similar height as normal controls (-0.46 ± 0.89 vs. -0.71 ± 1.67, p = 0.53), while the overweight/obese LI group was taller than the normal weight controls (0.36 ± 1.41 vs. -0.71 ± 1.67, p = 0.049), and of similar height as the overweight/obese controls (0.36 ± 1.41 vs. 0.87 ± 1.45, p = 0.28). MPTH z-score was similar between the groups.
  
  
  CONCLUSIONS
  Short stature and vitamin D deficiency are not features of LI in prepubertal children.
authors.affiliation: Department of Pediatrics, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors.forename: Nithya
authors.initials: N
authors.lastname: Setty-Shah
authors.forename: Louise
authors.initials: L
authors.lastname: Maranda
authors.forename: Ninfa
authors.initials: N
authors.lastname: Candela
authors.forename: Jay
authors.initials: J
authors.lastname: Fong
authors.forename: Idris
authors.initials: I
authors.lastname: Dahod
authors.forename: Alan D
authors.initials: AD
authors.lastname: Rogol
authors.forename: Benjamin Udoka
authors.initials: BU
authors.lastname: Nwosu
mesh_terms: D001827:Body Height; D015519:Bone Density; D002112:Calcifediol / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007787:Lactose Intolerance / Q000150:complications / Q000453:epidemiology* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D011627:Puberty; D014808:Vitamin D Deficiency / Q000150:complications*
chemical_list: D002112:Calcifediol