A new study shows lactose intolerance has no significant effect on stature or vitamin D status among children.
Lactose intolerance (LI) is characterized by the inability to digest and make use of dairy products. Dairy products contain a large source of calcium, which is important for bone growth and strength. Milk is also often fortified with vitamin D, because it is necessary to help absorb calcium in the gut.
Many studies have observed the effects of LI on calcium intake, levels and absorption, yet few have taken into account vitamin D levels among those with LI. For children, fortified milk provides some vitamin D. So in theory, if LI children are avoiding fortified milk, they might have low vitamin D levels.
In this new cross-sectional study, researchers compared vitamin D levels and overall stature between prepubertal children with LI and children without LI. In the study, 38 children with LI and 49 without LI enrolled.
Height was measured using mid-parental target height and blood samples were taken to determine vitamin D levels.
Researchers found no significant difference in serum vitamin D levels between children with LI and children without LI. Furthermore, they found no significant difference in height between LI children and the control group.
The researchers attributed this finding to the fact that sun exposure accounts for most vitamin D intake as opposed to food sources. Thus, if fortified milk contributes at all to vitamin D status in children, it is likely a small contribution.
A few limitations were cited in the study. The researchers stated that the cross-sectional design limits determination of causation on weight and vitamin D and stature. The study also sampled a small population size which may have attributed to the lack of significance. Additionally, the study didn’t measure dietary intake.
“We have shown that vitamin D deficiency is not a central feature of LI in prepubertal children,” the researchers stated. “Therefore, we concluded that LI does not have a significant effect on the overall stature or vitamin D status of affected children.”
Setty-Shah, N et. al. Lactose Intolerance Lack of Evidence for Short Stature or Vitamin D Deficiency in Prepubertal Children. PLOSOne, 2013.